  PHP HOW-TO
  Al Dev (Alavoor Vasudevan)            alavoor[AT]yahoo.com
  v27.6, 05 Oct 2002

  This document tells you howto develop PHP programs and also to migrate
  all the Windows 95 GUI applications to powerful PHP + HTML + DHTML +
  XML + Java applets + Javascript.  The information in this document
  applies to all the operating sytems where PHP is ported that is -
  Linux, Windows 95/98/NT/ME/2000/XP, BeOS, Apple Macintosh (is the son
  of FreeBSD Unix??), OS/2, all flavors of Unix like Solaris, HPUX, AIX,
  SCO, Unixware, Sinix, BSD, SunOS, etc..  and mainframe operating sys­
  tems and on all operating systems where "C" compiler is available.
  ______________________________________________________________________

  Table of Contents



  1. Introduction

  2. PHP runs on Microsoft Windows!!

  3. PHP Download

     3.1 PHP Installation on Microsoft Windows 95/98/NT/2000
     3.2 Apache Webserver Quick-Install (10 seconds) on Microsoft Windows 95/98/NT/2000
     3.3 SQL server for Microsoft
     3.4 ASP To PHP Converter - Migration From ASP2PHP
     3.5 PHP Installation on UNIX'es and others
     3.6 PHP Installation on Apple Macintosh

  4. Quick Start steps

  5. Major Features of PHP

     5.1 Advantages of PHP over Java
        5.1.1 Bad Points Of Java
        5.1.2 PHP works with Java
        5.1.3 PHP: Growing by the month

  6. Brief History of PHP

  7. A Simple Example

  8. SOAPX4 and PhpXMLP

     8.1 XML/XSLT Publishing Engine

  9. PHP Libraries

     9.1 Classes and PEAR
     9.2 Other PHP Utilities

  10. PHPGem package

  11. PHP Application Servers

     11.1 Build PHP based corporate Intranet and Internet
     11.2 Popular PHP Applications
     11.3 PHP Web Application Servers
     11.4 PHP Template Engines
     11.5 PHP based Web-Portal systems

  12. Object Oriented Features - public, private, protected

  13. HTML Editor

  14. IDE tools for PHP

     14.1 PHP IDE
     14.2 PHP IDE for MS Windows only
     14.3 PHP IDE for both MS Windows and Linux
     14.4 PHP IDE for Linux only
     14.5 PHP Utilities

  15. Code Protection - Encoding Source Code

  16. Convert Microsoft ASP scripts to PHP - ASP2PHP

  17. ctags for PHP

  18. PHP documenter (like Javadoc)

  19. Debugging PHP
     19.1 Debug with FILE and LINE

  20. General purpose programming with PHP

     20.1 Standalone MS Windows GUI applications using PHP

  21. Web Application Standards - Fusebox

  22. Performance benchmarking - PHP, ASP, JSP, Coldfusion

  23. Limitations of PHP

  24. PHP Tutorial

     24.1 Primer on PHP Sessions
     24.2 Session Management in PHP4
     24.3 Session Propagation
     24.4 User Management and Privileges
     24.5 Step1: Creating the Users Table

  25. PHP Training & PHP Help Desk

  26. Related URLs

  27. Other Formats of this Document

     27.1 Acrobat PDF format
     27.2 Convert Linuxdoc to Docbook format
     27.3 Convert to MS WinHelp format
     27.4 Reading various formats

  28. Copyright

  29. Appendix A PHP examples

     29.1 PostgreSQL large object Example
     29.2 User authentication Example
     29.3 Network admin Example

  30. Appendix B Midgard Installation

     30.1 Testing Midgard PHP Server
     30.2 Security OpenSSL

  31. Appendix C - Debug tool phpcodesite

  32. Appendix D - PERL versus PHP debate



  ______________________________________________________________________

  1.  Introduction

  (The latest version of this document is at
  <http://www.milkywaygalaxy.freeservers.com>. You may want to check
  there for changes).

  Definition: PHP is a simple, object-oriented, interpreted, robust,
  secure, very high-performance, architecture neutral, portable, dynamic
  scripting language. PHP has "class" keyword similar to Java's "class"
  keyword.  And PHP is designed such that it is 5 times faster than
  Java, since there is no virtual machine.  PHP is very fast becoming a
  standard, general purpose, object oriented scripting language.  PHP is
  not only meant for web applications but also can be used for
  developing general applications.
  PHP is the next big thing after HTML because today nobody writes
  static HTML but uses PHP (generate on the fly, embedded dynamic HTML).
  PHP 'kind-of' supercedes "static HTML".  PHP is a very powerful
  scripting language.  PHP will overtake PERL/Python and will replace
  PERL/Python.  PHP is the next-generation PERL/Python scripting.  PHP
  can do whatever PERL or Python does and actually does much more, much
  better and much, much cleaner.

  PHP stands for 'Hypertext Pre-Processor' and is a server side HTML
  scripting/programming language.  PHP is C-like Web scripting language
  runs on Apache, Netscape/iPlanet, and Microsoft IIS Web servers.  PHP
  is a tool that lets you create dynamic web pages. PHP-enabled web
  pages are treated just like regular HTML pages and you can create and
  edit them the same way you normally create regular HTML pages.  PHP
  lets you write simple scripts right in your HTML files much like
  JavaScript does, except, unlike JavaScript PHP is not browser-
  dependant. JavaScript is a client-side html-embedded language while
  PHP is a server-side language.  PHP is similar in concept to
  Netscape's LiveWire Pro product and Microsoft's ASP and Sun
  Microsystem's JSP.

  PHP is not only used for creating web applications, but also for
  creating general standalone applications.

  PHP's strength are :

  ·  PHP is the most superior technology. Other technologies PERL,
     Python, Tcl, VB script, ASP are older and inferior technologies.
     Even Java/JSP is inferior to PHP.

  ·  Open source

  ·  Easily learned syntax

  ·  Broad database connectivity

  ·  Massive library of contributed extensions

  ·  General purpose scripting language much superior to PERL, VB
     script, ASP, JSP.

  Why PHP ?  PHP is the best because of the following reasons:

  ·  PERL is the "ancestor" of PHP and PERL is used for a very long time
     (more than 25 years old?).  PHP has an advantage over PERL - PHP
     supports client-side code and is easier to compile into a
     executable. User base of PERL is very large.  PHP tries to imitate
     PERL and complement the PERL technology.  PERL programmers like
     PHP!  PHP is actually a "modern PERL", but with a  different name
     called "PHP".

  ·  Java is object-oriented but is very SLOW. Java programs run very
     slow.  Also Java is immensely complex and sophosticated technology
     (has many layers like JVM, JIT compiler and others). And complexity
     and sophostication leads to problems. If there is Linux on server-
     side then why do you need Java in servers ? And Java is more like a
     system programming language and it is faster to develop in
     scripting languages (like PHP).

  ·  Python is "good" but there are no C like brackets/braces which are
     useful for code navigation in vi editor. It is like your hand is
     broken if you cannot navigate rapidly the source code using
     vi/emacs editor's seek braces/brackets commands. PHP is
     technologically more advanced than Python.


  ·  PHP is the best because it is object oriented and has the best
     features of C/C++/Java/PERL/Python.  It can replace PERL, Python,
     Java, C, C++, awk, Unix shell scripting, MS Visual Basic and
     others!!  PHP runs direct and PHP is written in C.

  ·  Each and every computer programmer knows why PHP is the best.  Ask
     your nearby computer programmer.

  ·  Only PHP will prevail in the 21st and 22nd century and beyond!

  ·  Why do think every PERL, Python and Java programmers are flocking
     to PHP ?? There is a very strong reason.

  ·  Every person in the world wants PHP. PHP blast is causing shock-
     waves around the world!!

  ·  The world is dominated by PHP. There is PHP everywhere and
     anywhere... PHP, PHP, PHP everywhere..

  PHP was kept the "top secret and strictly confidential" computer
  language by many companies in the world, but now had become the most
  well-known and most widely used object oriented scripting language for
  web, internet, e-commerce, general purpose and business-to-business
  projects.  Even today many competing companies keep PHP language as a
  highly confidential matter not disclosing to outsiders (competitors).

  PHP will storm the entire world and will take the IT industry by
  surprise!!  The power of PHP is that it is cross-platform and runs
  everywhere!!  It runs on Linux, Windows 95/98/NT/2000/XP, Solaris,
  HPUX and all flavors of UNIX.  PHP is write once and deploy anywhere
  and everywhere.  It runs on many web-servers like Apache, Microsoft
  IIS, etc..

  PHP runs 5 to 20 times faster than Java!! In actual benchmarks, PHP
  was about 3.7 times faster than JSP (see ``''). PHP is extremely easy
  to use and you can develop very complex web/e-commerce/general-
  standalone applications very rapidly in a very short period of time.
  Developing applications in PHP is about TWO times faster than
  developing in programming language like Java (because there is no need
  for compilation in PHP).  (In future PHP language will imitate most
  features of Java language and Java programmers will love PHP. And PHP
  will have java keywords like class, extends, interface, implements,
  public, protected, private etc..).

  It has object oriented features and takes the best features from Java,
  C++, PERL and "C" languages. PHP language is a marriage of best
  features from Java, C++, PERL, Python and C.

  PHP is the real gem of all the scripting/programming languges and will
  soon become the "MECCA" for programmers world-wide!!  PHP has a huge
  user base and a large developer base as it runs on both
  Window95/NT/2000/XP and all flavors of UNIX'es.

  A big surprise is waiting for us - Most probably PHP will be the
  scripting language of the 21st century!!

  PHP can be compiled and optimized to make it run even faster by using
  the Zend Optimizer. Zend optimizer is integrated with PHP in PHP
  version 4.0.  First, you will write your application in PHP scripting
  language during development, testing and debugging. Once the project
  is ready for deployment you will use the Zend compiler to compile the
  PHP to create executable which will run very fast.

  You would normally use a combination of PHP (70% code) +
  HTML/DHTML/XML (25% code) + Javascript (5% code client side
  validations) for your e-commerce projects.
  2.  PHP runs on Microsoft Windows!!

  PHP initially started on UNIX platform, but it is very portable and
  runs on MS Windows and MS IIS webserver.  Today PHP has a large user
  base on MS Windows 2000/NT/95/98, You will find a huge collection of
  tools for PHP under MS Windows platform.

  Many PHP programmers develop code on MS Windows and deploy on large
  linux servers like IBM mainframe running linux, Compaq DEC Alpha and
  Sun sparc.

  A great advantage is that since PHP also runs on UNIX/Linux,
  developers on UNIX platform "cash on" the user base of PHP under MS
  windows as the PHP code developed under MS Windows can be used on
  UNIX/linux without any code change!!

  PHP itself is written in 100% "C" langauge, and hence it runs on a
  very wide variety of platforms like BeOS, UNIX, MS Windows, Apple
  Macintosh, IBM OS/2 and on many more operating systems.

  PHP is very fast and is much faster than Java. For web development,
  forget Java/JSP, it is PHP, PHP and PHP everywhere!! PHP is also
  becoming a general purpose object oriented scripting language



  3.  PHP Download


  ·  PHP main site  <http://www.php.net>

  ·  PHP resources  <http://ils.unc.edu/web-db/php/links.html>

  ·  PHP Code Exchange -  <http://px.sklar.com>

  ·  Vex Net  <http://www.vex.net/php>

  Mirror sites are in many countries like www.COUNTRYCODE.php.net, where
  COUNTRYCODE is like us, fe, sk etc.

  ·  <http://www.fe.de.php.net>

  ·  <http://www.sk.php.net>

  ·  <http://php.iquest.net/>

  ·  Questions e-mail to : rasmus@lerdorf.on.ca



  3.1.  PHP Installation on Microsoft Windows 95/98/NT/2000

  PHP is IMMENSELY POPULAR on Microsoft Windows platform and is
  surprisingly more popular than Microsoft's own ASP web scripting
  language!! A major reason for popularity is that PHP is a object
  oriented scripting language whereas ASP is not.  PHP has a large
  collection of re-usable classes (objects).  PHP runs lot faster than
  ASP on MS Windows and has more features and functionalities than
  Microsoft ASP.  PHP is much more robust, reliable and powerful than
  ASP.  And the user base of PHP is extremely large because PHP runs on
  MS Windows, Linux, Mac OS and all UNIX'es.  Greatest advantage of PHP
  is that you can develop on MS Windows and deploy on Linux or UNIX and
  vice versa!!

  There are more PHP users under MS Windows98/NT/2000 than on any other
  operating system!!  Because there is so much demand for PHP on MS
  Windows 98/NT/2000, a ready to install executable is made and you
  simply double-click on the exe file to automatically install PHP in
  just 2 minutes. Download the PHP executable install file from

  ·  MS Windows exe installer for PHP
     <http://php.weblogs.com/easywindows>

  ·  Lots of info on PHP on MS Windows platform
     <http://php.weblogs.com>

  ·  Install and config of PHP on MS Windows
     <http://www.php.net/manual/install-windows95-nt.php>

  ·  PHP Triad installs a complete PHP server environment on Windows
     platforms <http://www.phpgeek.com>



  3.2.  Apache Webserver Quick-Install (10 seconds) on Microsoft Windows
  95/98/NT/2000

  You need a web-server to run the PHP on MS Windows. You can use MS IIS
  web server or you can use free Apache web-server for MS Windows
  95/98/NT/2000. To save you lot of time here is the ready-to-install
  setup.exe file for apache for Windows platform:

  PHPTriad which is Apache+PHP+MySQL single package is at
  <http://www.phpgeek.com/phptriad.php> and at mirrorsite
  <http://sourceforge.net/projects/phptriad>.  I very strongly recommend
  PHPTriad as it is immensely popular among MS Windows users (millions
  of downloads).

  Apache binaries - <http://httpd.apache.org/dist/httpd/binaries/win32>



  3.3.  SQL server for Microsoft

  SQL server can be on a seperate box which need not be running MS
  Windows.  You also need a SQL server for doing web development. I
  recommend that you install Redhat Linux on a very old PC like (Pentium
  or 486 box) and install the PostgreSQL
  <http://www.geocities.com/alavoor/HOWTO/pgsql/PostgreSQL-HOWTO.html>
  RPMs on it. You do not need any windows graphics for a database server
  and at console mode startup the PostgreSQL
  <http://www.geocities.com/alavoor/HOWTO/pgsql/PostgreSQL-HOWTO.html>
  server.  PostgreSQL
  <http://www.geocities.com/alavoor/HOWTO/pgsql/PostgreSQL-HOWTO.html>
  is about 3 times faster than Oracle or MS SQL server.

  The PostgreSQL support code for PHP was written by Adam Sussman
  asussman@vidya.com

  You can also order ready-to-go cheap Linux boxes from -

  ·  Egghead Egghead <http://www.egghead.com>, click on Auctions and
     Linux boxes, you get best deals in live Auctions.

  ·  Goto LinuxHardware <http://lhd.datapower.com> and click
     ComputerSystems, LinuxOnline <http://www.linux.org/hardware>, Linux
     hardware Crynwr <http://linux.crynwr.com>, Linux HarwareNet
     <http://www.linuxhardware.net/vendors.html>

  ·  US Land5 <http://www.land-5.com/CustomPage4.html>, US QLiTech
     <http://www.qlitech.net/products/servers/athlon.html>, US
     CompaqLinux <http://www.compaq.com/products/servers/linux>, US
     VAlinux <http://www.valinux.com>, US StoreAnywhere
     <http://www.storeanywhere.com>

  ·  In Europe : UK GBdirect <http://www.gbdirect.co.uk/linux>, UK
     MultiT <http://www.multithread.co.uk>, Hungary Leonardo
     <http://www.leonardo.co.hu>, Belgium Mind <http://mind.be>, Germany
     Spier <http://www.spier.be>

  ·  DEC alpha linux DECalpha <http://www.alphalinux.org./hardware> and
     CompaqAlphaLinux
     <http://www.compaq.com/AlphaServer/linux/index.html>

  You can also get PostgreSQL
  <http://www.geocities.com/alavoor/HOWTO/pgsql/PostgreSQL-HOWTO.html>
  for Windows NT/2000 from  <http://www.askesis.nl>.

  See also the PostgreSQL
  <http://www.geocities.com/alavoor/HOWTO/pgsql/PostgreSQL-HOWTO.html>
  howto at pgsql-howto
  <http://www.geocities.com/alavoor/HOWTO/pgsql/PostgreSQL-HOWTO.html>


  3.4.  ASP To PHP Converter - Migration From ASP2PHP

  After installing PHP, you may want to migrate all the Microsoft ASP
  programs to PHP. See the chapter ``ASP2PHP''.



  3.5.  PHP Installation on UNIX'es and others

  See the installation guide and instructions at PHP main site
  <http://www.php.net> or INSTALL file in the downloaded package itself.



  3.6.  PHP Installation on Apple Macintosh

  Apple Macintosh is Unix like operating system. And actually it's
  father is FreeBSD.  It picked up many titbits from other Unices and is
  quite powerful OS.  See the Unix history at Unix Family Tree
  <http://perso.wanadoo.fr/levenez/unix> and click on the item 12 to see
  the Apple Mac position at Apple Mac tree
  <http://perso.wanadoo.fr/levenez/unix/history.html#12>.

  The installation and use of PHP on Apple Mac will be very similar to
  that of on Unix OS.



  4.  Quick Start steps

  To implement a project in object oriented PHP do -

  ·  First you need connection to database sql servers - use one of
     these:

  ·  ADODB (Active Data Objects Data Base)
     <http://php.weblogs.com/ADODB>

  ·  Metabase (Database independent access and management)
     <http://phpclasses.upperdesign.com/browse.html/package/20>



  ·  Second you need generic PHP classes to create forms, tables and
     other HTML objects. Get these from PHP classes at
     <http://phpclasses.upperdesign.com>.  See also the Top downloaded
     classes from Top PHP classes
     <http://phpclasses.upperdesign.com/browse.html/top>.  And see Form
     classes, template classes at the site corporate Intranet/Internet
     <http://www.milkywaygalaxy.freeservers.com>



  ·  Third, design and create your own PHP classes by inheriting from
     the generic PHP classes <http://phpclasses.upperdesign.com>.


  ·  Fifth, use IDE tools from ``''


  ·  Most of your PHP code should be in classes for easy code
     maintainence and re-usability.

  See also Aldev's PHP classes
  <http://phpclasses.upperdesign.com/browse.html/author/35463>



  5.  Major Features of PHP


  ·  Standard CGI, FastCGI and Apache module support - As a standard CGI
     program, PHP can be installed on any UNIX machine running any UNIX
     web server. With support for the new FastCGI standard, PHP can take
     advantage of the speed improvements gained through this mechanism.
     As an Apache module, PHP becomes an extremely powerful and
     lightning fast alternative to CGI programmimg.

  ·  Access Logging - With the access logging capabilities of PHP, users
     can maintain their own hit counting and logging. It does not use
     the system's central access log files in any way, and it provides
     real-time access monitoring. The Log Viewer Script provides a quick
     summary of the accesses to a set of pages owned by an individual
     user. In addition to that, the package can be configured to
     generate a footer on every page which shows access information. See
     the bottom of this page for an example of this.

  ·  Access Control - A built-in web-based configuration screen handles
     access control configuration. It is possible to create rules for
     all or some web pages owned by a certain person which place various
     restrictions on who can view these pages and how they will be
     viewed. Pages can be password protected, completely restricted,
     logging disabled and more based on the client's domain, browser, e-
     mail address or even the referring document.

  ·  PostgresSQL Support - Postgres is an advanced free RDBMS. PHP
     supports embedding PostgreSQL "SQL queries" directly in .html
     files.


  ·  RFC-1867 File Upload Support - File Upload is a new feature in
     Netscape 2.0. It lets users upload files to a web server. PHP
     provides the actual Mime decoding to make this work and also
     provides the additional framework to do something useful with the
     uploaded file once it has been received.

  ·  HTTP-based authentication control - PHP can be used to create
     customized HTTP-based authentication mechanisms for the Apache web
     server.

  ·  Variables, Arrays, Associative Arrays - PHP supports typed
     variables, arrays and even PERL-like associative arrays. These can
     all be passed from one web page to another using either GET or POST
     method forms.

  ·  Conditionals, While Loops - PHP supports a full-featured C-like
     scripting language.  You can have if/then/elseif/else/endif
     conditions as well as while loops and switch/case statements to
     guide the logical flow of how the html page should be displayed.

  ·  Extended Regular Expressions - Regular expressions are heavily used
     for pattern matching, pattern substitutions and general string
     manipulation. PHP supports all common regular expression
     operations.

  ·  Raw HTTP Header Control - The ability to have web pages send
     customized raw HTTP headers based on some condition is essential
     for high-level web site design. A frequent use is to send a
     Location: URL header to redirect the calling client to some other
     URL. It can also be used to turn off cacheing or manipulate the
     last update header of pages.

  ·  On-the-fly GIF image creation - PHP has support for Thomas
     Boutell's GD image library which makes it possible to generate GIF
     images on the fly.

  ·  ISP "Safe Mode" support - PHP supports an unique "Safe Mode" which
     makes it safe to have multiple users run PHP scripts on the same
     server.

  ·  Many more new features are being added in newer releases of PHP.
     Visit the main web site at  <http://www.php.net>

  ·  It's Free! - One final essential feature. The package is completely
     free.  It is licensed under the GNU/GPL which allows you to use the
     software for any purpose, commercial or otherwise.



  5.1.  Advantages of PHP over Java

  PHP is an established server-side scripting language for creating
  dynamic Web pages. As a language that has been designed expressly for
  the Web, it brings many features that commercial entities are looking
  for:

  ·  Exceptionally short learning curve

  ·  Quick development time

  ·  Very high performance

  This is essential for companies who are faced with scarce skilled
  programming resources and ever-tighter time to market deadlines. In
  addition, PHP supports all major platforms (UNIX, Windows and even
  mainframes), and features native support for most popular databases.
  All these factors make it a very good choice for Web development: such
  shops working with PHP have reported being able to hire non-
  programmers and have them producing usable code within days.
  Programmers familiar with languages such as C, C++ or Java frequently
  find that they can begin programming in PHP within a few hours.

  The fact that PHP was designed specifically for Web development gives
  it an edge as a development tool, as Intranet Design Magazine
  explains:

  "PHP was built with the needs of Web developers in mind... Unlike
  other cumbersome, overhead-laden approaches, PHP is lightweight and
  focused on the Web - where it can solve complex problem scenarios
  quicker and more easily than comparable technologies."1

  Java began its life as a programming language and was initially aimed
  at running client-side applications inside of Web browsers. Over the
  last few years, the problems associated with these "applets," as they
  were known, has led Sun and many other Java developers to use the
  language in other ways. One of the most prominent ways is in server-
  side programming, allowing Web sites to connect to databases and
  produce other server-side applications, or "servlets." Sun came out
  with Java Server Pages (JSP) as a means of writing servlets. JSP, like
  PHP, is highly portable across different platforms (even though PHP
  supports any 32-bit or better platform, whereas JSP supports only
  platforms that have a Java virtual machine available). However, a
  beginner with no programming background will find it exceptionally
  difficult to begin working with servlets,because of the complexity of
  the language as well as the complicated JSP system design.

  JSP's performance also leaves much to be desired: a recent survey in
  ZDnet's eWeek online publication found that PHP is as much as 3.7
  times faster than JSP. In the Web environment, this makes JSP a
  significantly worse solution - because it can perform less
  transactions per second, and features considerably slower response
  times.

  ZDnet's eWeek also noted that

  "JSP is a relatively new technology and still has clear market
  immaturities in terms of tools, support resources and available
  talent."...Because JSP is based on Java, a strongly typed language, we
  had to declare the types of variables we used and manually convert
  between types when necessary. This makes JSP the hardest of the
  scripting languages we tested for nonprogrammers to learn..."



  5.1.1.  Bad Points Of Java


  1. The server is under your control but you will never know what the
     clients will be?  MS Windows, Linux, Mac, Unix?? Java is designed
     for client side computing with "Applets", "Swing" and "AWT".



  2. Java is a bad choice on the server-side! Since server OS is under
     your control, you need something like PHP which runs directly
     without any intermediate layers like Java virtual machine and JIT
     compiler. You simply select Linux, Unix or MSWindows on server-side
     and use PHP.



  3. Java is very complicated due to many layers like JVM, JIT, whereas
     PHP is quite simple, fast and runs directly on the server operating
     system. This means Java technologies can never be faster than PHP!



  4. Java technology is very bad choice on the server-side. When you
     have Linux on server which is completely under your control why do
     you need Java?? By the way, the browser clients never know that you
     are using Linux + Apache + PHP !! (The clients may think that the
     HTML pages are coming from MS Windows + MS IIS !! )



  5. Use Java technology on the client-side. Use Java inside web
     browsers like Applets and other client applications like Swing, AWT
     and others.



  5.1.2.  PHP works with Java

  It is important to note JSP is just one language with which Java
  objects can be accessed. PHP also can also integrate with Java, which
  means that it can be used as the scripting language for activating
  Java logic, just as much as JSP can. Unlike JSP, however, PHP also
  integrates with other component models, such as Microsoft's COM, and
  adding support for new object models is extremely easy. This means
  PHP's extensibility is infinite. JSP, on the other hand, is completely
  dependent on Java.

  IBM programmer Sam Ruby uses PHP in combination with Java. Using the
  native Java support in PHP, Java objects can be created and used
  transparently, as if they were regular PHP objects.

  AuctionWatch , which enables businesses of all sizes to benefit from
  dynamic pricing environments, has over 2.6 million unique visitors per
  month; 300K+ registered users; 1.2 million+ auctions launched every
  month. They tried to use Java, but opted for PHP because it's easier
  to use and much faster to develop with. For further information,
  please contact Ben Margolin, Director of Seller Services for
  AuctionWatch (ben@auctionwatch.com).

  Programming consultant Reuven Lerner has made some comparisons among
  the languages. His view of PHP is summarized as follows:

  "The language is easy to learn. Graphic artists and Web designers
  might claim that they are not programmers, but the fact is that
  they're doing increasingly large projects in JavaScript, VBScript, and
  other simple programming languages. PHP is much more regular and well-
  defined than PERL, and is much easier for new programmers to grasp
  than Java. Indeed, PHP seems like a server-side version of what
  JavaScript could have been, but isn't. Someone with little or no
  programming experience can learn PHP and work with it after a very
  short period of time. This is probably true for VBScript, but
  certainly not for PERL or Java....PHP is a truly remarkable and
  powerful system.  I can see why it has become a popular system for
  producing Web sites.... I think that it will be a very strong
  competitor against Java and JSPs, and will rise significantly in my
  recommendations for clients and internal use."



  5.1.3.  PHP: Growing by the month

  JSP enjoys the backing of Sun; hence its constant media attention. It
  is interesting to note that despite the lack of any publicity
  campaign, PHP's popularity is growing at a monthly rate of 8-11%, a
  percentage far greater than the Internet's 4% monthly growth -- as the
  demand for server-based applications has risen. More than 6.5 million
  sites use PHP (Netcraft May 2001 survey). PHP is used on 39% of Apache
  servers; PERL trails fourth, with 11% of the market.  Apache maintains
  59% of the Web server market; Microsoft IIS is second, with 28% of
  market share (E-Soft Inc./SecuritySpace's May 2001 report).

  Prominent corporations using PHP include Unilever, Philips, NTT,
  Cisco, Japan Airlines, Air Canada, Lufthansa, GE Marketplace,
  Wallstreet:Online Germany; AuctionWatch, VillageVoice, Dialpad and
  BMC.


  1. Intranet Design Magazine: PHP From an IT Manager's Perspective, Jun
     4, 2000.
     <http://linuxtoday.com/news_story.php3?ltsn=2000-06-04-002-04-NW-
     HL-SW>


  2. eWEEK: Four scripting languages speed development, October 30,
     2000.
     <http://www.zdnet.com/eweek/stories/general/0,11011,2646052,00.html>



  6.  Brief History of PHP

  PHP began life as a simple little cgi wrapper written in PERL.  The
  name of this first package was Personal Home Page Tools, which later
  became Personal Home Page Construction Kit.

  Old name is Professional Home Pages (PHP) and new name is PHP
  Hypertext Pre-Processor.

  A tool was written to easily embed SQL queries into web pages. It was
  basically another CGI wrapper that parsed SQL queries and made it easy
  to create forms and tables based on these queries. This tool was named
  FI (Form Interpreter).

  PHP/FI version 2.0 is a complete rewrite of these two packages
  combined into a single program.  It evolved to a simple programming
  language embedded inside HTML files.  PHP eliminates the need for
  numerous small PERL cgi programs by allowing you to place simple
  scripts directly in your HTML files. This speeds up the overall
  performance of your web pages since the overhead of forking PERL
  several times has been eliminated.  It also makes it easier to manage
  large web sites by placing all components of a web page in a single
  html file.  By including support for various databases, it also makes
  it trivial to develop database enabled web pages. Many people find the
  embedded nature much easier to deal with than trying to create
  separate HTML and CGI files.

  Now PHP/FI is renamed as PHP.



  7.  A Simple Example

  Suppose you have a form:


       <FORM ACTION="/cgi-bin/php.cgi/~userid/display.html" METHOD=POST>
       <INPUT TYPE="text" name="name">
       <INPUT TYPE="text" name="age">
       <INPUT TYPE="submit">
       <FORM>



  Your display.html file could then contain something like:


       < ?echo "Hi $ name, you are $ age years old!<p>" >



  It's that simple! PHP automatically creates a variable for each form
  input field in your form. You can then use these variables in the
  ACTION URL file.

  The next step once you have figured out how to use variables is to
  start playing with some logical flow tags in your pages. For example,
  if you wanted to display different messages based on something the
  user inputs, you would use if/else logic. In our above example, we can
  display different things based on the age the user entered by changing
  our display.html to:


       <?
           if($age>50);
               echo "Hi $name, you are ancient!<p>";
           elseif($age>30);
               echo "Hi $name, you are very old!<p>";
           else;
               echo "Hi $name.";
           endif;
       >



  PHP provides a very powerful scripting language which will do much
  more than what the above simple example demonstrates. See the section
  on the PHP Script Language for more information.

  You can also use PHP to configure who is allowed to access your pages.
  This is done using a built-in configuration screen. With this you
  could for example specify that only people from certain domains would
  be allowed to see your pages, or you could create a rule which would
  password protect certain pages. See the Access Control section for
  more details.

  PHP is also capable of receiving file uploads from any RFC-1867
  compliant web browser. This feature lets people upload both text and
  binary files. With PHP's access control and logical functions, you
  have full control over who is allowed to upload and what is to be done
  with the file once it has been uploaded. See the File Upload section
  for more details.


  PHP has support for the PostgreSQL database package. It supports
  embedded SQL queries in your .HTML files.

  PHP also has support for the mysql database package. It supports
  embedded SQL queries in your .HTML files.



  8.  SOAPX4 and PhpXMLP

  SOAP is an XML-based protocol for messaging and RPC-style
  communication between two processes.  The World Wide Web Consortium's
  XML Protocol (XP) Working Group is working on a SOAP standard, which
  will be called XP.

  The SOAPX4 (Simple Object Access Protocol) implementation for PHP is
  at <http://dietrich.ganx4.com/soapx4>.

  Alternate SOAP implementation is at
  <http://sourceforge.net/projects/phpxmlp>.



  8.1.  XML/XSLT Publishing Engine

  Krysalis is the XML/XSLT publishing engine, inspired from Cocoon but
  adapted to the PHP technology.

  InterAKT has developed Krysalis to achieve what the next generation of
  web services have to offer -  the complete separation of the
  information, application logic and presentation layer.

  Krysalis is an open-source PHP development platform, based on the
  XML/XSLT core. It reused most of PHAkt code to create the Krysalis
  taglib library.

  Major features are:

  ·  Dynamic XML support.

  ·  Dynamic PDF generation.

  ·  Sitemap description with regular expressions.

  ·  PXP page caching.

  ·  Multiple transformation pipelines.

  ·  Multiple connection types to various databases (ADODB).

  Please visit the Krysalis site for more information
  <http://www.interakt.ro/products/Krysalis>.



  9.  PHP Libraries

  The PHP is a object-oriented scripting language. Hence PHP code is
  "classes, classes, classes and classes". When you write PHP code you
  must design your classes such that they are re-usable or they use
  existing PHP classes.  There are hundreds of PHP classes already
  written and ready to use. There are classes for accessing databases,
  classes for generating XML, HTML forms, classes for creating tables,
  forms and other HTML objects. If you write some generic classes then
  please upload to sites. By year 2005, there will be more than hundred
  million re-usable PHP classes. Advantage of PHP classes are they
  provide - data hiding, inheritance, encapsulation, reliability,
  reusability and polymorphism.  The most important PHP sites are PHP
  classes and PEAR as given below.



  9.1.  Classes and PEAR

  Visit the following web sites which have large collections of ready to
  use PHP class libraries.

  ·  PHP classes are at  <http://phpclasses.upperdesign.com>.


  ·  PEAR (PHP Extension and Application Repository) is a code
     repository for PHP extensions and PHP library code similar to
     PERL's CPAN and is at <http://pear.php.net> and mirror
     <http://lxr.php.net/source/php4/pear> linux php-pear-rpms
     <http://rpmfind.net/linux/rpm2html/search.php?query=pear> and pear-
     tutorials <http://php.weblogs.com/php_pear_tutorials>.



  ·  ADODB (Active Data Objects Data Base)
     <http://php.weblogs.com/ADODB> : PHP's database access functions
     are not standardised. Every database extension uses a different and
     incompatibile API. This creates a need for a database class library
     to hide the differences between the different databases
     (encapsulate the differences) so we can easily switch databases.
     ADODB currently support MySQL, PostgreSQL
     <http://www.geocities.com/alavoor/HOWTO/pgsql/PostgreSQL-
     HOWTO.html> , Interbase, Oracle, MS SQL 7, Foxpro, Access, ADO,
     Sybase and generic ODBC.  See also ADODB-manual
     <http://php.weblogs.com/ADODB_manual>.  The PhpLens
     <http://phplens.com> is based on ADODB.



  ·  Metabase (Database independent access and management)
     <http://phpclasses.upperdesign.com/browse.html/package/20>


  ·  PHP Hot scripts  <http://www.hotscripts.com/PHP>


  ·  Very popular PHP resources  <http://php.resourceindex.com> and CGI-
     Resources <http://cgi-resources.com>


  ·  PHP projects are at  <http://php.net/projects.php>


  ·  PHP Lib Netuse  <http://phplib.netuse.de> (This is deprecated,
     merged with PEAR)

  ·  PHP widgets  <http://www.northern.ca/projects/phpwidgets>

  ·  Generic Framework PHP4  <http://sourceforge.net/projects/gpfr>

  ·  Source Forge PHP Lib  <http://phplib.sourceforge.net>

  ·  Source Forge PHP Snippets, go and click on PHP here
     <http://sourceforge.net/snippet>

  ·  E-gineer PHP lib  <http://e-gineer.com/articles/php-hacker>

  ·  FAQ PHP  <http://php.faqts.com>

  ·  PHP Lib  <http://px.sklar.com>

  ·  PHP Factory  <http://alfalinux.sourceforge.net/phpfact.php3>



  ·  PHP Builder site  <http://phpbuilder.com/snippet>

  ·  PHP developer  <http://www.phpdeveloper.org>

  ·  PHP newbie  <http://www.newbienetwork.net>

  ·  PHP walrus  <http://www.evilwalrus.com>



  9.2.  Other PHP Utilities

  Other PHP utilities are at :

  ·  User Login sample:
     <http://www.devshed.com/Server_Side/PHP/Commerce1>


  ·  phpPDFtable is a class written in php to ease the creation of
     tables in PDF files. It requires php (4.0 but should run with 3.x
     too), and pdflib  <http://sourceforge.net/projects/phppdftable>


  ·  Data-Admin aims to provide a PHP based interface to Database
     Administration. This will not be limited to just one or two
     databases. Also, the underlying class library encapsulates the
     native PHP database calls allowing the programmer to use one set of
     fu <http://sourceforge.net/projects/dadmin>


  ·  PSlib is a PHP library for generating PostScript files. It offers
     an easy way of generating PostScript files: simple call PSlib
     functions from within your PHP script and the PS files are created
     on the fly <http://sourceforge.net/projects/pslib>


  ·  A complete collection of php scripts that work tightly together to
     create a highly customizable, dynamic and module oriented website
     <http://sourceforge.net/projects/twebs>


  ·  phpOpenTracker is a comprehensive solution for your site- and
     visitor-tracking needs. The collected data is stored in a SQL
     database, allowing complex, yet easy analysis. A powerful API for
     analysis and report generation (HTML or PDF output) is included.
     <http://www.phpopentracker.de>


  ·  PHPShopCart is a shopping-cart web application demo written in PHP
     and designed to connect to a MySQL database. It was written for the
     book, "A Guide to Databases under Linux" (Syngress Media) but is
     available under the GNU Public License.
     <http://sourceforge.net/projects/phpshopcart>



  10.  PHPGem package

  PHPGem is a PHP-script which accelerates the creation of PHP-scripts
  for working with tables. It works with different SQL-servers such as
  PostgreSQL, MySQL, mSQL, ODBC, and Adabas. You input a description of
  and parameters for your tables' fields (field name, on/off searching
  in the field, etc.), and PHPGem outputs another PHP-script which will
  work with the tables (view/add/edit/delete/duplicate entries and
  search). PHPGem works with multi-level nested tables. PHPGem allows
  you to specify a level of access for each table and for each field for
  each user. PHPGem also support images.

  PHPGem is at  <http://sptl.org/phpgem>



  11.  PHP Application Servers

  The PHP applications are categorized into more than 60 groups in
  hotscripts.com site at HotScripts - PHP
  <http://www.hotscripts.com/PHP/Scripts_and_Programs>.  You MUST visit
  this site before looking elsewhere.



  11.1.  Build PHP based corporate Intranet and Internet

  Visit the site corporate Intranet/Internet
  <http://www.milkywaygalaxy.freeservers.com> for a very good comparison
  and listing of applications.



  11.2.  Popular PHP Applications

  The most popular PHP applications in the order are:

  1. PHP-Nuke <http://www.hotscripts.com/Detailed/5947.html> and the
     mainsite <http://phpnuke.org>

  2. Smarty <http://www.hotscripts.com/Detailed/8817.html> and the
     mainsite <http://www.phpinsider.com/php/code/Smarty>

  3. eZ Publish <http://www.hotscripts.com/Detailed/7894.html> and the
     mainsite <http://developer.ez.no/article/static/7>

  4. Mambo Portal/Content Mgmt
     <http://www.hotscripts.com/Detailed/10068.html> and the mainsite
     <http://www.miro.com.au>

  5. PHP Content Management System
     <http://www.hotscripts.com/Detailed/8455.html> and the mainsite
     <http://mcyra.homeip.net/homepage/phpcms/index.htm>

  6. PHP Shop <http://www.hotscripts.com/Detailed/4131.html> and the
     mainsite <http://www.phpshop.org>

  7. phpWebSite <http://www.hotscripts.com/Detailed/9026.html> and the
     mainsite <http://phpwebsite.appstate.edu>

  8. myPHPCalendar <http://www.hotscripts.com/Detailed/4182.html> and
     the mainsite <http://myPHPCalendar.sourceforge.net>

  9. TreeMenu <http://www.hotscripts.com/Detailed/3704.html> and the
     mainsite <http://apollo.spaceports.com/~refcentr/index.html>

  10.
     Backend <http://www.hotscripts.com/Detailed/5921.html> and the
     mainsite <http://back-end.org>

  11.
     Typo3 Content Mgmt <http://www.hotscripts.com/Detailed/8392.html>
     and the mainsite <http://www.typo3.com>

  12.
     E-Guest <http://www.hotscripts.com/Detailed/9956.html>

  13.
     PHProjekt <http://www.hotscripts.com/Detailed/7598.html> and the
     mainsite <http://www.phprojekt.com/index.php>

  14.
     Phorum <http://www.hotscripts.com/Detailed/175.html> and the
     mainsite <http://phorum.org>

  PHP has several tools which are given below:



  11.3.  PHP Web Application Servers

  The following are available for PHP:

  ·  LogiCreate WebApp Server (for PHP)

     The LogiCreate system was designed primarily with  open source
     technologies of Linux, Apache and PHP, LogiCreate provides a unique
     value in price/performance and costs are kept reasonable. Visit
     <http://www.logicreate.com> and click on Download button and read
     the white papers there.


  ·  PHP Lens <http://phplens.com> is a rapid application development
     component which allows PHP developers to dynamically and quickly
     create web applications that retrieve information from databases.
     With phpLens, data can be presented as html tables with facilities
     to create, edit, paginate, search and delete records. PHPLens uses
     ADODB.  See also ADODB <http://php.weblogs.com/ADODB>.



  ·  ADODB (Active Data Objects Data Base)
     <http://php.weblogs.com/ADODB> : PHP's database access functions
     are not standardised. Every database extension uses a different and
     incompatibile API. This creates a need for a database class library
     to hide the differences between the different databases
     (encapsulate the differences) so we can easily switch databases.
     ADODB currently support MySQL, PostgreSQL
     <http://www.geocities.com/alavoor/HOWTO/pgsql/PostgreSQL-
     HOWTO.html> , Interbase, Oracle, MS SQL 7, Foxpro, Access, ADO,
     Sybase and generic ODBC.  See also ADODB-manual
     <http://php.weblogs.com/ADODB_manual>.
  ·  Metabase (Database independent access and management)
     <http://phpclasses.upperdesign.com/browse.html/package/20>



  ·  Binary Cloud <http://www.binarycloud.com> is an opensource,
     enterprise class web application platform It provides a complete
     set of core services such as authentication, permissions, database
     abstraction, and error handling - and a rich set of advanced tools
     built on that foundation.

     The system is deployed in a number of commercial installations and
     has proven to be robust, scaleable, and secure.  Binarycloud is
     suitable for large-scale commerce and publishing projects, or
     anything of similar complexity. It offers some unique security
     features - such as selective encryption of database I/O - which
     make it a particularly good choice for web applications that
     require a high level of data security. And it's free.



  ·  PEAR (PHP Extension and Application Repository) is a code
     repository for PHP extensions and PHP library code similar to
     PERL's CPAN and is at <http://lxr.php.net/source/php4/pear> and
     pear-tutorials <http://php.weblogs.com/php_pear_tutorials>.



  ·  Midgard is Content management system is based on Apache and uses
     the PHP scripting language The main site of Midgard is at
     <http://www.midgard-project.org> PHP can be compiled with Zend
     compiler and optimizer  <http://www.zend.com>. PHP runs very fast
     and is about 5 to 10 times faster than Java.

     See ``Midgard Installation''



  ·  Ariadne <http://www.muze.nl/software/ariadne> is a web application
     system. It consists of a complete framework for the easy
     development and management of web applications, using PHP. The
     system uses a modular approach, using abstract interfaces for all
     transactions. This results in maximum freedom to change parts of
     the systems workings or add new functionality without needing to
     reprogram other parts



  ·  Group IT Engine <http://groupit.org> is a turnkey group
     collaboration and content management engine. It presently runs on
     UNIX machines using PHP and Apache. Using GroupIT you can
     "Categorize your content", "Organize your contents into sections",
     "Control access to your content" and many more additional features
     <http://groupit.org/channel/features>.



  ·  Ampoliros <http://www.ampoliros.com> Ampoliros is an advanced and
     easy to use distributed PHP Web applications platform, featuring a
     powerful Xml-Rpc and Soap interface. It is suitable as an
     Internet/Intranet development and deployment system. It has a very
     strong modular architecture and allows very fast deployment of web
     solutions.  Ampoliros is backed by Solarix, which offers
     customization, complete Ampoliros based solutions, support,
     developer programs and other services.

  11.4.  PHP Template Engines


  ·  Php Sitemanager - do code creation, a layout design, site
     implementation and site management. Visit SiteManager
     <http://www.roadsend.com/siteManager/home/treeMenu.php>



  ·  Smarty Template Engine - is a template engine for PHP. One of the
     unique aspects about Smarty that sets it apart from other
     templating solutions is that it compiles the templates into native
     PHP scripts upon the first invocation. After that, it merely
     executes the compiled PHP scripts. Therefore, there is no costly
     template file parsing for each request.

     See Smarty QuickStart
     <http://www.phpinsider.com/php/code/Smarty/QUICKSTART> and docs
     about Smarty are at
     <http://www.phpinsider.com/php/code/Smarty/docs>.  Get it from
     download-smarty <http://www.phpinsider.com/php/code/Smarty>.



  ·  DreamTime Template  <http://www.phptemplates.org>



  ·  Fast Template <http://curtisonline.net/theme/phpfast-templates-
     HOWTO.html> and main-site <http://www.thewebmasters.net>



  ·  PHP template Layout classes commercial, VH Layout
     <http://www.vhconsultants.com> and see this-article
     <http://www.phpbuilder.com/columns/zhang19990610.php3>



  11.5.  PHP based Web-Portal systems

  The following ready-made Web-Portal systems are available:

  ·  PHP Nuke Web Portal system at PhpNuke
     <http://sourceforge.net/projects/phpnuke>


  ·  DarkPortal is a Web portal system similar to PHPNuke. It is based
     on the user interface style of Slashdot and other news/portal
     systems.  It uses a modular core as a base for adding pluggable
     modules to facilitate content creation and management. Its primary
     goals are full separation of content from code, fully modular
     portal plugins with standardized APIs, portability and database
     abstraction, user level theme selection and plugin module
     selection, and a modular user/group hierarchy with multiple levels
     of moderation and admin capabilities.  Visit DarkPortal
     <http://freshmeat.net/redir/darkportal/13912/url_homepage>


  ·  CMS system ezPublish <http://developer.ez.no>


  ·  Mambo is a feature-rich, dynamic portal engine/content management
     tool based on PHP/MySQL. It features a very powerful and extensive
     admin manager, and uses a modular framework for extensibility.
     Visit Mambo <http://www.mamboserver.com> and mirror
     <http://www.miro.com.au>


  ·  Content Management system (CMS) PostNuke at  <http://postnuke.com>



  12.  Object Oriented Features - public, private, protected

  PHP scripting language provides object oriented features through the
  class keyword.  Features like public, private and protected will be
  supported in the future release (they are in TODO list). In the
  meantime, you can use the following coding conventions to distinguish
  between private, public and protected variables:

  1. All private variables and functions always start with underscore
     "_" followed by lowercase letters like var $_myvar;


  2. All Protected variables and functions always start with "_T"
     followed by lowercase letters like var $_Tmyvar;


  3. All Public variables and functions do not start with underscore "_"
     like var $myvar;


  4. All variables and functions always start with lowercase letter (no
     uppercase) like var $_myvar; and NOT like var $_Myvar;


  ______________________________________________________________________
  class someabc {
          var $_conn;                     // Private variable
          var $_Tmyvar;                   // Protected variable
          var $connMYCONNECTION;          // Public variable
          var $connToDb;                  // Public variable
          var $myvar3;                    // Public variable
          var $myvarTHISTEST;             // Public variable

          function _foofunction() {}      // Private function
          function _Tfoofunction() {}     // Protected function
          function foofunction() {}       // Public function
  }
  ______________________________________________________________________



  The private, protected declarations provide the encapsulation and
  data-hiding.  But you must consider the following disadvantages of
  encapsulation:

  ·  Encapsulation usually requires more code, hence it sacrifices
     performance especially for scripting languages like PHP


  ·  Encapsulation requires lots of Set/Get methods for
     private/protected properties.


  ·  Since encapsulation unneccessarily increases the code size, it is
     not recommended for scripting language like PHP.



  ·  You can enforce a good degree of encapsulation by using the coding
     convention suggested in this section.



  13.  HTML Editor

  HTML editors for PHP on Windows 95/NT/2000 are:

  ·  1st Page 2000 - Rated 1st (the best HTML editor)
     <http://www.evrsoft.com>

  ·  Cool Page - Rated 2nd  <http://www.coolpage.com>

  ·  Coffeecup - Rated 3rd  <http://www.coffeecup.com/editor>

  ·  Arachnophilia - Rated 4th
     <http://www.arachnoid.com/arachnophilia/index.html>

  ·  Textpad  <http://www.textpad.com> and textpad-php-add-ons
     <http://www.textpad.com/add-ons/files/syntax/php4.zip>

     The best HTML editor is 1st Page 2000, and it is a excellent HTML
     editor.



  14.  IDE tools for PHP

  Many HTML editors are supporting PHP.  In near future every HTML
  editors and XML editor will be supporting PHP "Rapid Application
  Development" tool.

  You will notice that some of the PHP editors run only on MS Windows.
  Yes!!  there are millions of PHP developers on MS Windows platform.
  PHP is IMMENSELY POPULAR on Microsoft Windows platform and is
  surprisingly more popular than Microsoft's own ASP web scripting
  language!!  PHP runs lot faster than ASP on MS Windows and has more
  features and functionalities than Microsoft ASP.  PHP is much more
  robust, reliable and powerful than ASP.  There are more PHP users
  under MS Windows98/NT/2000 than on any other operating system!!  PHP
  initially started on Linux/UNIX environment but today there are more
  PHP developers on MS Windows platform as compared to UNIX.



  14.1.  PHP IDE

  PHP IDE  tools are at :

  ·  PHAktThe PHP support in Macromedia Dreamweaver UltraDev that allows
     Ultradev Developers to create PHP sites PHAkt
     <http://www.interakt.ro/products/PHAkt>

  ·  PHP Lens <http://phplens.com> is a rapid application development
     component which allows PHP developers to dynamically and quickly
     create web applications that retrieve information from databases.
     With phpLens, data can be presented as html tables with facilities
     to create, edit, paginate, search and delete records. PHPLens uses
     ADODB.  See also ADODB <http://php.weblogs.com/ADODB>.

  ·  PHP IDE and Editor "PHP Coder" is now renamed to Maguma and is
     available at <http://www.maguma.com/english/index.php>

  ·  HAPEdit at  <http://hapedit.free.fr>

  ·  Cross-platform IDE : Activestate Komodo
     <http://www.activestate.com/Products/Komodo>

  ·  Zend PHP IDE  <http://zend.com/store/products/zend-ide.php>

  ·  IDE for PHP scripting (Web Browser) :
     <http://www.ekenberg.se/php/ide>

  ·  Nexidion PHP IDE   <http://www.nexidion.org>

  ·  Enter in Search keyword 'PHP IDE' in Source Forge
     <http://sourceforge.net>

  ·  Color editor gvim for PHP (Win and linux) at
     <http://metalab.unc.edu/LDP/HOWTO/Vim-HOWTO.html> and see also
     ``ptags of PHP''



  14.2.  PHP IDE for MS Windows only

  PHP IDE/editor on MS Windows platform are :

  ·  Rated 1st (the best PHP tool on MS Windows) : PHPTriad is a
     complete PHP development and server environment for Windows. It
     installs PHP, Apache, MySQL, and PHPMyAdmin, both installing and
     setting up the environment. PHPTriad is at
     <http://www.phpgeek.com/phptriad.php> and at mirrorsite
     <http://sourceforge.net/projects/phptriad>

  ·  Rated 2nd : PHP Coder  <http://www.php-ide.com>

  ·  Rated 3rd: PHPEd (Soyal), an excellent PHP editor (MS Windows)
     <http://soysal.free.fr/PHPEd>


  ·  IDE for PHP editor (MS Windows):  <http://www.phpedit.com>

  ·  Color editor gvim for PHP (Win and linux) at
     <http://metalab.unc.edu/LDP/HOWTO/Vim-HOWTO.html> and see also
     ``ptags of PHP''

  ·  IDE for PHP (MS Windows)  <http://www.pc-service-
     boerner.de/PHPScriptEditor.htm>

  ·  "EditPlus Text editor" win32  <http://www.editplus.com> (high
     rating 5 stars)

  ·  eNotepad win32
     <http://www.edisys.com/Products/eNotepad/enotepad.asp> (high rating
     5 stars)

  ·  PHP editor win32  <http://www.chami.com/html-kit> (high rating 5
     stars)

  ·  UltraEdit win32  <http://www.ultraedit.com> with PHP word file at
     <http://www.ultraedit.com/downloads/additional.html>

  ·  ScriptWorx editor win32
     <http://www.softlite.net/products/scriptworx> (rating 4.5 stars)

  ·  TextPad editor win32  <http://www.textpad.com> (rating 4.5 stars)


  ·  PHP editor "ASPEdit"  <http://www.tashcom.com/aspedit> (rating 3.5
     stars) along with PHP code explorer  <http://www.tashcom.com/codex>
     (rating 4.5 stars)

  ·  Code-genie editor similar to UltaEdit or TextPad but smaller in
     size  <http://www.code-genie.com>

  ·  HTML/PHP editor Dreamweaver  <http://www.dreamweaver.com>

  ·  HTML/PHP editor Homesite  <http://www.allaire.com/homesite>

  ·  HTML/PHP editor Hotdog  <http://www.hotdog.com>



  14.3.  PHP IDE for both MS Windows and Linux

  PHP IDE/editor for bot MS Windows and Linux platforms are :

  ·  PHP editor (for both windows and linux/UNIX)
     <http://www.coffeecup.com/select/editor.html> (rating 5 stars).

  ·  HTML/PHP editors Amaya  <http://www.w3.org/Amaya>

  ·  Folding text editor (Win and linux)  <http://fte.sourceforge.net>

  ·  PHP Editor (Win and linux)  <http://www.scintilla.org>

  ·  Color editor gvim for PHP (Win and linux) at
     <http://metalab.unc.edu/LDP/HOWTO/Vim-HOWTO.html> and see also
     ``ptags of PHP''

  ·  Jed (win and linux)  <http://space.mit.edu/~davis/jed.html>


  ·  Editors for PHP :  <http://www.itworks.demon.co.uk/phpeditors.htm>

  ·  Editors for PHP :
     <http://www.oodie.com/tools/index.php?view=editor>



  14.4.  PHP IDE for Linux only

  The best IDE for PHP on linux is Coffeecup Editor as given below:

  ·  Color editor gvim for PHP (Win and linux) at
     <http://metalab.unc.edu/LDP/HOWTO/Vim-HOWTO.html> and see also
     ``ptags of PHP''

  ·  PHP editor <http://www.coffeecup.com/select/editor.html> (rating 5
     stars).

  ·  HTML/PHP editors Quanta  <http://quanta.sourceforge.net>

  ·  HTML/PHP editors Blue Fish  <http://bluefish.linuxave.net>

  ·  HTML editors AswEdit  <http://www.advasoft.com>



  14.5.  PHP Utilities

  Zend is a server-side caching software speeds up Web site performance,
  maximizes hardware resources, and improves the online experience of
  customers, providing a good return on investment. Zend accelerator
  caches PHP scripts, helping to reduce processing time and Web server
  load while enabling administrators to  monitor site performance in
  real time.  Cost is $980 and supports Linux, Solaris and FreeBSD.
  Zends provides:

  ·  Enables IT to serve more Web site visitors with existing hardware

  ·  Speeds up Web site response time

  ·  Provides real-time performance monitoring


  ·  Zend Optimizers  <http://www.zend.com>

  ·  Zend Compilers  <http://www.zend.com>


  ·  IonCube PHP Accelerator (PHPA)  <http://www.php-accelerator.co.uk>
     The ionCube PHP Accelerator is an easily installed PHP Zend engine
     extension that provides a PHP cache, and is capable of delivering a
     substantial acceleration of PHP scripts without requiring any
     script changes, loss of dynamic content, or other application
     compromises.


  ·  APC "Alternative PHP Cache" is an open-source alternative to Zend's
     commercial accelerator which is at
     <http://apc.communityconnect.com>.


  ·  Lots of info on PHP on MS Windows platform
     <http://php.weblogs.com>


  ·  PHP GroupWare Apps  <http://www.phpgroupware.org>

  ·  PHP Web Shop  <http://www.phpshop.org>

  ·  PHP Nuke Web Portal system PhpNuke
     <http://sourceforge.net/projects/phpnuke>



  15.  Code Protection - Encoding Source Code

  If you want to distribute your PHP source code to your clients, you
  may want to encode it to protect your code so that it cannot be viewed
  by the users.  Use encoding to hide password, encode scripts etc.
  Many enterprises require securing the source code as a pre-condition
  for release process.

  Use one of the following Encoding tools:

  ·  PHP encoding with Zend Encoder
     <http://www.zend.com/store/products/zend-encoder.php>


  ·  PHP encoding with IonCube Encoder
     <http://www.ioncube.com/encoder/index.php>



  16.  Convert Microsoft ASP scripts to PHP - ASP2PHP

  To convert ASP scripts to PHP  use this utility
  <http://asp2php.naken.cc>

  See also  <http://www.asp2php.com>



  17.  ctags for PHP

  Tags are extremely valuable and are used for navigation of source code
  inside the editors like vi, emacs, CRiSP, NEdit etc... If you had
  programmed a lot in C, C++ or Java you might have used the ctags
  program to create tags.  To see the online manual page, type 'man
  ctags' at linux/UNIX bash prompt.  The latest version of ctags
  supports PHP language and is available from
  <http://ctags.sourceforge.net>.

  NOTE: Do NOT use the ptags given below but instead use the latest
  ctags which supports PHP language. The program below is just a
  exercise and sample and was created when older versions of ctags did
  not support PHP. The listing below is kept for historical reasons (a
  musuem).

  The ptags program for PHP is given below, which you can use to create
  the tags for PHP source code. Your productivity will improve 3 to 4
  times if you use ptags.

  See also Vim color text editor for PHP, C, C++ at
  <http://metalab.unc.edu/LDP/HOWTO/Vim-HOWTO.html>



  ______________________________________________________________________
  // Save this file as ptags.cpp and compile by
  //              g++ -o ptags ptags.cpp
  //*****************************************************************
  // Copyright policy is GNU/GPL but additional request is
  // that you include author's name and email on all copies
  // Author : Al Dev Email: alavoor[AT]yahoo.com
  // Usage : ptags *.php3 *.inc
  //                 This will generate a file called tags
  //*****************************************************************
  #include <iostream.h>
  #include <fstream>
  #include <stdio.h> // for sprintf
  #include <stdlib.h> // for system
  #include <string.h> // for memset
  #include <ctype.h> // for isspace

  #define BUFF_LEN  1024
  #define LOCATION  9

  char *ltrim(char *dd);
  char *rtrim(char *ee);

  main(int argc, char **argv)
  {
          if (argc < 2)
          {
                  cerr << "\nUsage: " << argv[0] << " file .... " << endl;
                  exit(0);
          }

          char fname[100] = "tag_file.out";
          FILE    *fpout;
          ofstream    fout(fname);
          if (fout.fail())
          {
                  cerr << "\nError opening file : " << fname << endl;
                  exit(-1);
          }
          //fpout = fopen(fname, "w");

          for (int ii = 1; ii < argc; ii++)
          {
                  /*
                  char buff[2024];

                  sprintf(buff, "\\rm -f %s; ls %s > %s 2>/dev/null", outfile, argv[1], outfile);
                  cout << "\nbuff = " << buff << endl;

                  system(buff);
                  fclose(fp);
                  */
                  FILE *fpin = NULL;
                  fpin = fopen(argv[ii], "r");
                  if (fpin == NULL)
                  {
                          cerr << "\nError opening file : " << argv[ii] << endl;
                          exit(-1);
                  }
                  char buff[BUFF_LEN + 100];
                  memset(buff, 0, BUFF_LEN +10);
                  for ( ; fgets(buff, BUFF_LEN, fpin) != NULL; )
                  {
                          char aa[BUFF_LEN + 100];
                          char aapointer[BUFF_LEN + 100];
                          memset(aa, 0, BUFF_LEN +10);
                          strcpy(aa, buff);
                          strcpy(aapointer, ltrim(aa));
                          strcpy(aa, aapointer);

                          // Remove the trailing new line..
                          {
                                  int tmpii = strlen(aa);
                                  if (aa[tmpii-1] == '\n')
                                          aa[tmpii-1] = 0;
                          }
                          //cout << "aa is : " << aa << endl;
                          //cout << "aapointer is : " << aapointer << endl;
                          if (strncmp(aa, "function ", LOCATION) != 0)
                                  continue;
                          //cout << buff << endl;

                          // Example tags file output is like -
                          // al2  al.c    /^al2()$/;"   f
                          {
                                  char bb[BUFF_LEN + 100];
                                  memset(bb, 0, BUFF_LEN +10);
                                  strcpy(bb, & aa[LOCATION]);
                                  char *cc = bb;
                                  while (cc != NULL && *cc != '(')
                                          *cc++;
                                  *cc = 0;
                                  cc = rtrim(bb);
                                  //cout << "bb is : " << bb << endl;
                                  //cout << cc << "\t" << argv[ii] << "\t" << "/^" << aa << "$/;\"\tf" << endl;
                                  fout << cc << "\t" << argv[ii] << "\t" << "/^" << aa << "$/;\"\tf" << endl;
                                  //fprintf(fpout, "%s\t%s\t/^%s$/;\"f\n", cc, argv[ii], aa );
                          }

                          memset(buff, 0, BUFF_LEN +10);
                  }
                  fclose(fpin);
          }
          fout.flush();
          fout.close();
          //fclose(fpout);

          // Sort and generate the tag file
          {
                  char tmpaa[1024];
                  sprintf(tmpaa, "sort %s > tags; \\rm -f %s", fname, fname);
                  system(tmpaa);
          }
  }

  char *ltrim(char *dd)
  {
      if (dd == NULL)
          return NULL;

      while (isspace(*dd))
          dd++;

          return dd;
  }

  char *rtrim(char *ee)
  {
      if (ee == NULL)
          return NULL;

          int tmpii = strlen(ee) - 1;
          for (; tmpii >= 0 ; tmpii--)
          {
                  if (isspace(ee[tmpii]) )
                  {
                          //cout << "\nis a space!!" << endl;
                          ee[tmpii] = 0;
                  }
          }
          return ee;
  }
  ______________________________________________________________________



  18.  PHP documenter (like Javadoc)


  ·  The phpDocumentor is a script for creating documentation from
     comments in php code.  It is at  <http://phpdocu.sourceforge.net>.


  ·  The Doxygen documentation <http://www.stack.nl/~dimitri/doxygen>
     system can be used along with this Doxygen PHP PERL
     <http://www.stack.nl/~dimitri/doxygen/download.html#latestman>
     script. Download Doxygen and the PERL script from download page.


  ·  PHPXref is a small PERL script to make working with the source code
     of a large PHP site somewhat easier.  Cross references functions,
     variables and database tables defined and used across your various
     PHP files Generates documentation for each function defined in the
     PHP files by utilizing formatted comments placed next to each
     function The output is a tree of HTML files that can be downloaded
     and browsed on a local machine without having to setup a web
     server, etc.  It is at  <http://phpxref.sourceforge.net>.



  19.  Debugging PHP

  You can use one of the following debuggers.

  List of PHP debuggers :

  ·  <http://download.php.net/manual/en/debugger.php>.

  ·  <http://dd.cron.ru/dbg>

  ·  Zend-IDE has PHP debugger
     <http://www.zend.com/store/products/zend-ide.php>

  ·  Soysal editor has PHP debugger  <http://www.soysal.com/PHPEd>

  ·  APD (Advanced PHP Debugger)  <http://apd.communityconnect.com>

  ·  PHP symbolic debugger
     <http://members.ozemail.com.au/~djf01/body.html> and at
     <http://freshmeat.net/projects/body-phpdebugger>

  ·  Cross-platform IDE : Activestate Komodo
     <http://www.activestate.com/Products/Komodo>


  ·  The PHP Symbolic Debugger called Body
     <http://members.ozemail.com.au/~djf01/body.html>

  ·  PHP Debugger called 'phpCodeSite' is available at
     <http://phpcodesite.phpedit.com> and see also ``Appendix C''

  ·  Code crusader  <http://www.newplanetsoftware.com/jcc>

  ·  PHP Debugger is available at  <http://www.phpdebug.com>



  19.1.  Debug with FILE and LINE

  To debug PHP programs create a file "debug2.inc" having the following
  functions :



  ______________________________________________________________________
  <?php

  /* define this variable, to prevent double declaration. */
  if (!defined("_DEBUG2_DEFINED_"))
  {
          define("_DEBUG2_DEFINED_", 1 );
  }
  else
          return; // if this file is already included then return

  # file name : debug2.inc
  # Functions for debuging the PHP source code
  #*****************************************************************
  # Copyright policy is GNU/GPL but additional request is
  # that you include author's name and email on all copies
  # Author : Al Dev Email: alavoor[AT]yahoo.com
  #*****************************************************************

  # Usage of this functions -
  # In your source code put something like -
  # debug2_(__FILE__, __LINE__, "f_somevariable", $f_somevariable);
  # And this will generate output in debug.out file.

  //function debug2_($fname, $lname, $debug_var, $debug_value=0) {}

  // Give read, exec for all on directory /debug2_logs
  // chmod a+rwx /debug2_logs
  // But here you need to open the file in append mode.
  $fp_debug2 = fopen("/debug2_logs/debug.out", "a");
  if ($fp_debug2 == false)
  {
          print "<b>File open failed - global.var.inc<b>";
          exit;
  }

  function debug2_($fname, $lname, $debug_var, $debug_value=0)
  {
          global $fp_debug2;

          //print "<br> debug_value is : $debug_value <br>";
          if (!$debug_value)
          {
                  fwrite($fp_debug2, "\n ". $fname ."  ". $lname .": $debug_var");
          }
          else
          {
                  fwrite($fp_debug2, "\n ". $fname . " ". $lname .": $debug_var = $debug_value");
          }
          //print "<br> f_cookie is : $f_cookie <br>";
  }

  // In your first page, which is generally index.php3
  // truncate the debug2_logs file in beginning of code
  function init_debug_file()
  {
          global $fp_debug2;

          $fp_debug2 = fopen("/debug2_logs/debug.out", "w");
          if ($fp_debug2 == false)
          {
                  print "<b>File open failed - global.var.inc<b>";
                  exit;
          }
          system("chmod a+rwx /debug2_logs/debug.out");
  }
  ?>
  ______________________________________________________________________



  In your PHP source code initial page which is generally index.php3,
  put a line like

  ______________________________________________________________________
  <?php
          include ("debug2.inc");

          init_debug_file();
          // all other commands follows here ...
          // ...........
  ?>
  ______________________________________________________________________



  To output debug values, in your PHP source code files, put debug2_()
  calls as illustrated below:

  ______________________________________________________________________
  <?php
  include ("debug2.inc");
  debug2_(__FILE__, __LINE__, "f_somevariable", $f_somevariable);

  function aa()
  {
          $aa = 8;
          debug2_(__FILE__, __LINE__, "aa", $aa);
  }
  ?>
  ______________________________________________________________________



  When you run the PHP program the output will be traced in the file
  called debug.out giving the filename, linenumber, variable name and
  it's value.

  Use the debug2_() generously in your code. The usage of debug2_()
  calls in your program will NOT have any impact on the final production
  code and also has no impact on the performance because they will be
  filtered out as described below. You can use copy and paste to save
  time of typing debug2() calls or use the 'yank to buffer' feature of
  Vi editor and paste.

  When you are done development and testing and when you are ready to
  deploy on the production server, filter out the debug2_ calls from
  your source code. At UNIX prompt -

  ______________________________________________________________________
  bash$ mkdir production
  bash$ grep -v debug2_  filea.php3 > production/filea.php3
  ______________________________________________________________________


  For a large group of files -



  ______________________________________________________________________
  bash$ mkdir production
  bash$ ls *.php3 | while read ans
  do
          grep -v  debug2_ $ans > production/$ans
  done
  ______________________________________________________________________


  And now copy the files from production to the deployment area.



  20.  General purpose programming with PHP

  PHP is very powerful and is designed such that it can replace awk,
  sed, UNIX shell, PERL, Python, "C", C++ and Java.


  The object oriented features of PHP is developing very rapidly and in
  near future will surpass the object oriented features of Java
  language. All the object oriented features are implemented in PHP via
  class keyword just like in Java.

  If you build the CGI version of PHP, you can use it from the command
  line simply typing: php filename where filename is the file you want
  to parse. You can also create standalone PHP scripts by making the
  first line of your script look something like:


           #!/usr/local/bin/php -q



  The "-q" suppresses the printing of the HTTP headers. You can leave
  off this option if you like.

  If you want to use PHP as a stand-alone program, just like a shell
  script, "C" or PERL program, then use this technique:

  ______________________________________________________________________
  bash$ php -q filename.php
  bash$ php -h
  bash$ php -?
  bash$ /usr/bin/php -?
  bash$ php -i
  ______________________________________________________________________


  The command php filename.php will execute the file filename.php.  You
  are invoking the php program which you wrote in filename.php from the
  bash commmandline instead of from the web-browser.

  On Microsoft Windows platform you will bringup a MSDOS prompt from
  Start->Run->cmd and put C:\Program Files\php\bin in your path
  environment and



  ______________________________________________________________________
  C:\> php -q filename.php
  C:\> php -h
  C:\> php -?
  or
  C:\> c:\Program Files\php\bin\php filename.php
  ______________________________________________________________________



  20.1.  Standalone MS Windows GUI applications using PHP

  Since PHP is general purpose scripting language and is like a "glue"
  language, you can use it develop standalone MS Windows GUI
  applications.  PHP can be very easily combined with MS Windows C++ GUI
  classes to create GUI applications. And developing applications with
  PHP is extremely fast as it is a scripting language and it's runtime
  performance is also excellent as compared with other scripting
  languages like PERL, Visual Basic and Python.

  PHP can also be used for developing standalone GUI applications for
  Linux/UNIX'es.



  21.  Web Application Standards - Fusebox

  Fusebox is a FREE web application standard attempting to reduce the
  70% software failure rate by creating a standard methodology for
  writing web applications. This development methodology works with ANY
  web application small and large.

  ·  Fusebox Org <http://www.fusebox.org>

  ·  PHP-Fusebox development <http://php-fusebox.sourceforge.net>

  ·  <http://bombusbee.com>

  ·  Techsedition <http://www.techspedition.com>

  ·  <http://www.fusebox.com>

  ·  <http://www.devshed.com/Server_Side/PHP/Fusebox>



  22.  Performance benchmarking - PHP, ASP, JSP, Coldfusion

  It is very important to bear in mind that performance and running
  speed of the web scripting engine must be given TOP PRIORITY. That is,
  how many pages per second the scripting engine can pump out to the
  browser clients. The greater the number of pages pumped out to clients
  in a given period of time, then the better and more powerful the
  scripting engine is.

  The Zdnet
  <http://www.zdnet.com/enterprise/stories/linux/0,12249,2646052,00.html>
  did a evaluation and benchmarking of 4 web scripting languages. During
  benchmarking, the same spec and identical cpu, memory boxes were used.
  Under identical conditions, it was found that PHP was the fastest -
  about 3.7 times faster than JSP and about 1.2 times faster than ASP.
  Read the report at eWeek
  <http://www.zdnet.com/enterprise/stories/linux/0,12249,2646052,00.html>
  and mirror-site <http://24.221.230.253/php-asp-jsp-cf.html> The
  benchmark results are -

  ·  PHP pumped out about 47 pages/second

  ·  Microsoft ASP pumped out about 43 pages/second

  ·  Allaire ColdFusion pumped out about 29 pages/second

  ·  Sun Java JSP pumped out about 13 pages/second

  See also PHP, ASP benchmarks at  <http://24.221.230.253/php-perl-
  benchmarks.html>

  Whenever you design a web site, give attention to these important
  points:

  ·  Speed of web scripting engine - how many pages per second it can
     pump out.



  ·  KISS policy (Keep It Simple Stupid!!) - your web page should be
     very simple without any fancy graphics (because web users do not
     want to wait for long time and they want the information very
     fast). And information they read is just plain text!!



  23.  Limitations of PHP

  Everything has limitations or disadvantages and PHP is no exception.
  The following are the limitations of PHP (so be WARNED !!)

  1. PHP is NOT 100 % pure Object Oriented scripting language.  But in
     near future PHP may support 100%  object oriented scripting (PHP
     may imitate most of the syntax of Java language). PHP already
     imitates some features of Java language.  (In future PHP language
     will imitate most features of Java language and Java programmers
     will love PHP. And PHP will have java keywords like class, extends,
     interface, implements, public, protected, private etc..).

  2. PHP will NOT give the performance of "C" or "C++" language. Because
     it is scripting language and is interpreted it will be a bit slower
     than the optimized "C++" programs. For top performance, you should
     use "C++" and fast-CGI with database/webserver connection pooling
     and use C++ compiler optimizer "-O3" options.  Zend optimizer in
     PHP 4 will speed up the performance of PHP and bring it very close
     to optimized "C" code .

  3. But note a point that PHP was designed for very Rapid Web-
     Application Development tool. If it takes about 3 months to code a
     web application in C++, then using PHP you can develop the same web
     application in just 4 days!!  And with zend optimizer, the speed of
     execution of PHP will be very close to that of equivalent C++
     program!! Hence, there is really no advantage in using C/C++ for
     web development. PHP itself is written in 100% "C" language.

  On the other hand, PHP has lot of advantages and it's advantages
  outweigh it's limitations -

  1. You can very rapidly develop web applications in PHP as compile and
     link is eliminated in PHP scripting language.

  2. PHP applications are very stable and do not depend on the browser
     technologies unlike Javascript applications which depend on
     browsers.  PHP will give you the freedom to select any server
     platform. The browser does not know that the HTML page is generated
     by PHP !!

  3. PHP has excellent database conectivity to all SQL database servers.

  4. PHP has partial support for Object oriented features

  5. PHP has C++, PERL, Javascript like syntax features and has programs
     like

  6. PHP has Zend optimizer which speeds up the performance

  7. PHP runs on all UNIX'es, linux, Windows 95/NT/2000 and is more
     powerful than ASP, JSP and others.

  8. PHP has a very large user base and developer base.

  See also Python:  If you want 100% pure Object Oriented scripting
  language than you MUST consider Python. The 'Python' is a object
  oriented scripting language from ground up. You would be using the
  Python Web Application server called 'Zope' which is available at -
  <http://www.zope.org> and python is at <http://www.python.org>



  24.  PHP Tutorial

  Visit the following PHP tutorial sites -

  ·  PHP Resource index - important PHP site - has complete scripts,
     Functions, classes, documentation, examples and tutorials
     <http://php.resourceindex.com>

  ·  PHP portal  <http://zend.com>


  ·  PHP Hot scripts site  <http://www.hotscripts.com/PHP>


  ·  Very popular PHP resources  <http://php.resourceindex.com> and CGI-
     Resources <http://cgi-resources.com>


  ·  Simple tutorial  <http://www.php.net/tut.php>

  ·  Web Monkey
     <http://hotwired.lycos.com/webmonkey/99/21/index2a.html>

  ·  Dev Shed  <http://www.devshed.com/Server_Side/PHP/Introduction>

  ·  PHP TidBits  <http://www.htmlwizard.net/resources/tutorials>

  ·  PHP Builder  <http://www.phpbuilder.com/getit>

  ·  PHP tutorials at  <http://www.cgi-network.net>

  ·  LinuxGuruZ PHP tutorials at  <http://www.linuxguruz.org>

  ·  PHP Wizard  <http://www.phpWizard.net>

  In this tutorial we assume that your server has support for PHP
  activated and that all files ending in .php are handled by PHP.  If
  you are using Apache then you should edit httpd.conf and make
  appropriate changes to enable PHP.

  Your first PHP-enabled page: Create a file named hello.php and in it
  put the following lines:

  ______________________________________________________________________
  <html>
  <head>
  <title>
  PHP Test</title>
  </head>
  <body>
  <h1>
  This is an example of php script.
  <br>
  Below, you will see one line saying 'Hello World' and 'foo is foobar':
  </h1>
  <?php
  echo "Hello World";
  $foo = "foobar";
  echo "<br>foo is $foo";
  ?>
  </body>
  </html>
  ______________________________________________________________________



  Copy this file hello.php to the directory known to Apache, like
  /var/www/html which is also known as DocumentRoot in httpd.conf file.
  Now, to run this example, bring up a web browser and type the URL
  http://localhost/hello.php or you can type http://127.0.0.1/hello.php.
  But make sure you bring up Apache web server on your system.  When you
  run the example you will get an output like:

  ______________________________________________________________________
  This is an example of php script.
  Below, you will see one line saying 'Hello World' and 'foo is foobar':

  Hello World
  foo is foobar
  ______________________________________________________________________


  If you get some errors or if you see the file with tags then your
  Apache Web server may not be working properly or PHP is not enabled.

  Note that this is not like a CGI script.  Think of it as a normal HTML
  file which happens to have a set of special tags available to you.

  If you tried this example and it didn't output anything, chances are
  that the server you are on does not have PHP enabled. Ask your
  administrator to enable it for you.

  The point of the example is to show the special PHP tag format. In
  this example we used < ?php to indicate the start of a PHP tag. Then
  we put the PHP statement and left PHP mode by adding the closing tag,
  ? > . You may jump in and out of PHP mode in an HTML file like this
  all you want.

  We are going to check what sort of browser the person viewing the page
  is using. In order to do that we check the user agent string that the
  browser sends as part of its request. This information is stored in a
  variable. Variables always start with a dollar-sign in PHP. The
  variable we are interested in is $HTTP_USER_AGENT.  To display this
  variable we can simply do:

  ______________________________________________________________________
        <?php echo $HTTP_USER_AGENT; ?>
  ______________________________________________________________________



  For the browser that you are using right now to view this page, this
  displays:

  Mozilla/4.0 (compatible; MSIE 4.01; Windows 98)

  There are many other variables that are automatically set by your web
  server. You can get a complete list of them by creating a file that
  looks like this:

  ______________________________________________________________________
        <?php phpinfo()?>
  ______________________________________________________________________



  Then load up this file in your browser and you will see a page full of
  information about PHP along with a list of all the variables available
  to you.

  You can put multiple PHP statements inside a PHP tag and create little
  blocks of code that do more than just a single echo.

  ______________________________________________________________________
        <?php
        if(strstr($HTTP_USER_AGENT,"MSIE")) {
            echo "You are using Internet Explorer<br>";
        }
        ?>
  ______________________________________________________________________



  We can take this a step further and show how you can jump in and out
  of PHP mode even in the middle of a PHP block:


  ______________________________________________________________________
          <?php
          if(strstr($HTTP_USER_AGENT,"MSIE"))
          {
                  ?>
                  <center><b>You are using Internet Explorer</b></center>
                  <?
          }
          else
          {
                  ?>
                  <center><b>You are not using Internet Explorer</b></center>
                  <?
          }
          ?>
  ______________________________________________________________________


  Instead of using a PHP echo statement to output something, we jumped
  out of PHP mode and just sent straight HTML. The important and power­
  ful point to note here is that the logical flow of the script remain
  intact. Only one of the HTML blocks will end up getting sent to the
  viewer. Running this script right now results in:

  You are using Internet Explorer

  Dealing with Forms

  One of the most powerful features of PHP is the way it handles HTML
  forms.  The basic concept that is important to understand is that any
  form element in a form will automatically result in a variable with
  the same name as the element being created on the target page. This
  probably sounds confusing, so here is a simple example. Assume you
  have a page with a form like this on it:

  ______________________________________________________________________
        <form action="action.php3" method="POST">
        Your name: <input type=text name=name>
        You age: <input type=text name=age>
        <input type=submit>
        </form>
  ______________________________________________________________________


  There is nothing special about this form. It is a straight HTML form
  with no special tags of any kind. When the user fills in this form and
  hits the submit button, the action.php3 page is called. In this file
  you would have something like this:

  ______________________________________________________________________
        Hi <?php echo $name?>.  You are <?php echo $age?> years old.
  ______________________________________________________________________


  Surprise!! The $name and $age variables are automatically set for you
  by PHP !!



  24.1.  Primer on PHP Sessions

  This section is written by Ying Zhang  .

  Before we begin, let's quickly go over the concept of a session and
  the reason we need it. It's hard (for me) to define what a session is
  exactly, so let's use an example that should be very familiar to you
  -- logging in to your computer and using it every day. After you log
  in, your computer knows who you are. Every action that you perform is
  done so with your name.

  So what's so special about that -- we take it for granted every time
  we have to login to any system. What's the big deal with doing this on
  the web? Well, the web (or specifically, the HTTP protocol) is
  connectionless. That means each request made to a web server is
  independent of all the other requests. Whereas your computer keeps
  information about you in memory and knows when you log in and out, a
  web server doesn't. A web server simply waits for requests and sends
  responses.

  Let's illustrate this a little bit:



  ______________________________________________________________________
  John Doe           __________         Jane Doe
    1               |          |            2
    3  ------------>|web server|<---------- 4
    5               |__________|            6
  ______________________________________________________________________



  Let's say we only have two people, John Doe and Jane Doe, accessing
  MyMarket, and their actions are like this:


  1. John looks at the product catalog.

  2. Jane looks at the product catalog.

  3. John adds an item to his basket.

  4. Jane adds an item to her basket.

  5. John goes to the checkout.

  6. Jane goes to the checkout.

  Since HTTP is connectionless, each request is completely isolated from
  the other requests. So how does the server know who's doing what? How
  does the server know that actions 1, 3, 5 are from John, and actions
  2, 4, 6 are from Jane? Well, to make a long story short, the web
  server doesn't have to know. It can continue on happily responding to
  requests, session management has to be done with the backend scripting
  language.

  What we need is a way to group together requests by the same person
  into the same session. This is where PHP4's session management
  capabilities come in. It can group together requests made from the
  same source (eg. client's browser) into the same session, we have to
  provide the smarts to associate users with sessions.

  In other words, PHP4's session management can tell us requests 1, 3,
  and 5 belong to the same session (call it session A). Our application
  has to know that session A is owned by John Doe.



  24.2.  Session Management in PHP4

  PHP4 adds some session management functions that make our life easier
  when dealing with sessions. The ones we are interested in are:

  ______________________________________________________________________
  session_start();
  session_register();
  ______________________________________________________________________



  session_start() is used to start up PHP4's session management
  capabilities; you need to call it before you use any of the other
  session functions. session_register() is used to tell PHP which
  variables to track in the session. A typical call to these functions
  would look like this:

  session_register("SESSION");


  This tells PHP to start up the session manager, and tells PHP that the
  variable called SESSION is a session variable. You can register as
  many session variables as you like, but I prefer to only register one
  session variable called SESSION, and anything I need persistent I put
  into this variable. For example, I like to say:


  ______________________________________________________________________
  session_register("SESSION");
  $SESSION["var1"] = 5;
  $SESSION["var2"] = 6;
  ______________________________________________________________________



  instead of

  ______________________________________________________________________
  session_register("var1");
  session_register("var2");
  $var1 = 5;
  $var2 = 6;
  ______________________________________________________________________


  because after you register lots of session variables, you tend to for­
  get what they were, well, at least I do :).

  Anyhow, by now you probably want to see some code in action, so create
  a script called session_test.php somewhere accessible, and put into
  it:


  ______________________________________________________________________
  <?
  session_start();
  session_register("SESSION");

  if (! isset($SESSION)) {
          $SESSION["count"] = 0;
          echo "<li>Counter initialized, please reload this page to see it increment";
  } else {
          echo "<li>Waking up session $PHPSESSID";
          $SESSION["count"]++;
  }
  echo "<li>The counter is now $SESSION[count] ";
  ?>
  ______________________________________________________________________



  Fire that up in your browser, the first time you hit the page, it
  should say " Counter initialized, please reload this page to see it
  increment". Each time you reload it, the counter value should
  increment by one. You will also see the session ID. If it does, then
  hurray, your PHP4 session manager works :)

  So how does this work? Well, when you call session_start(), PHP4
  determines a unique session ID for the client. This session ID is an
  MD5 hash of something (not sure what), and is either stored in a
  cookie on the client's PC or is propagated in the URL.


  Now each time that client makes a request, PHP4 will read this session
  ID and load up the data for the session. When you call
  session_register(), you are telling PHP4 which variables you want kept
  in the session. Each page that loads up, the previous values for the
  registered variables will be reloaded, and each time the page ends
  PHP4 will save the values of the registered variables.

  By default, PHP keeps track of the sessions in temporary files in the
  /tmp directory. If you leave this set to a world-readable directory,
  such as /tmp (the default), other users on the server may be able to
  hijack sessions by getting the list of files in that directory.

  session.save_path defines the argument which is passed to the save
  handler. If you choose the default files handler, this is the path
  where the files are created. Defaults to /tmp.

  Take a listings and see for yourself:

  You will see something like this:


  ______________________________________________________________________
  -rw-------   1 apache   web            10 May  7 15:27 sess_6dd9ea8e61cd49cd3ad6de8c8b8885e8
  -rw-------   1 apache   web            10 May  7 19:49 sess_7d7f97afb6759948f554b00272494e52
  -rw-------   1 apache   web             6 May  9 01:00 sess_8ab78830e151add9d79b628958ce4eb9
  -rw-------   1 apache   web            31 May  9 11:41 sess_a3058a6bb1baf57f565c3844c8810f4b
  -rw-------   1 apache   web            30 May  9 11:42 sess_c379faad83ad3dc8ab6d22c14dbab3b4
  -rw-------   1 apache   web             6 May  8 01:00 sess_cd68a5054241aff1a8157c289683e869
  -rw-------   1 apache   web            34 May  7 15:17 sess_cd97e41912b28c44cc0481b7d978cb61
  -rw-------   1 apache   web            42 May  9 11:23 sess_d1285edd0c951c70b1aec17a5f602fc0
  -rw-------   1 apache   web            30 May  9 11:42 sess_da93f6e19b6be01257d7a6453766a23d
  -rw-------   1 apache   web            42 May  7 21:26 sess_e837123c1af78c538e89b47030fde337
  ______________________________________________________________________



  Each one of those files is a session, let's take a look at one of them
  (note, you probably have to su to root to peek inside a session file).
  Tip: don't just cut and paste the following commands, you need to
  specify the name of a real file:


  ______________________________________________________________________
  # more /tmp/sess_a3058a6bb1baf57f565c3844c8810f4b
  ______________________________________________________________________



  You will see something like this:


  ______________________________________________________________________
  SESSION|a:1:{s:5:"count";i:234;}
  ______________________________________________________________________



  Does that look familiar? It should if you've ever used the serialize()
  and unserialize() functions in PHP. If not, don't worry about it.
  Anyhow, I just wanted to illustrate how sessions were stored. You can
  rewrite the PHP session handlers to store sessions into a database or
  whatever else, but that's beyond the scope of this tutorial (but it's
  not hard at all).



  24.3.  Session Propagation

  There are two methods to propagate a session id:

  ·  Cookies


  ·  URL parameter

     The session module supports both methods. Cookies are optimal, but
     since they are not reliable (clients are not bound to accept them),
     we cannot rely on them. The second method embeds the session id
     directly into URLs.

  PHP is capable of doing this transparently when compiled with
  --enable-trans-sid. If you enable this option, relative URIs will be
  changed to contain the session id automatically. Alternatively, you
  can use the constant SID which is defined, if the client did not send
  the appropriate cookie. SID is either of the form
  session_name=session_id or is an empty string.

  The following example demonstrates how to register a variable, and how
  to link correctly to another page using SID.

  Example : Counting the number of hits of a single user

  ______________________________________________________________________
  <html>
  <h1>Example : Counting the number of hits of a single user</h1>
  <br>
  <php
  session_register ("count");
  $count++;
  ?>

  Hello visitor, you have seen this page <?php echo $count; ?> times.<p>;

  <php
  # the <?=SID?> is necessary to preserve the session id
  # in the case that the user has disabled cookies
  ?>

  To continue, <A HREF="nextpage.php?<?=SID?>">click here</A>
  <html>
  ______________________________________________________________________


  The <?=SID?> is not necessary, if --enable-trans-sid was used to com­
  pile PHP.

  Note: Non-relative URLs are assumed to point to external sites and
  hence don't append the SID, as it would be a security risk to leak the
  SID to a different server.



  24.4.  User Management and Privileges

  Okay, we've spend enough time on PHP4's session management, all you
  really need to get out of that was the two functions session_start()
  and session_register(). Let's get back to the issue of keeping track
  of users.

  PHP can help us keep track of sessions, and group requests from the
  same session together. Now, we have to do our part and associate user
  accounts with these sessions. We will use a variable called
  SESSION["user"] to keep track of user information. When a user logs
  in, we will put their information into this variable. As long as this
  variable is defined, we will assume that a user has logged in. When a
  user logs off, we will clear out this variable.

  Specifically, we will keep the following information about the user:


  ______________________________________________________________________
  SESSION["user"]["username"] This is the user's login ID (their nick name if you will), and it is how we tell users apart from each other.
  SESSION["user"]["firstname"] The user's firstname.
  SESSION["user"]["lastname"] The user's lastname.
  SESSION["user"]["email"] The user's email address.
  SESSION["user"]["priv"] The user's privilege level.
  ______________________________________________________________________



  Let's talk a bit about the privilege levels. We are going to have two
  levels of security: (1) normal customers and (2) administrative users.
  Normal customers can use the system, browse through the catalog, and
  do other customer functions. Administrators can do everything a normal
  user can do, but also has the ability to perform system administrative
  functions. In real life, there are probably many more privilege levels
  that you want defined but we are going to keep things simple here.

  This is all fine and dandy, but where do we get this user information
  from? We need to have a way to store all the users on the system, and
  the perfect place for that would be in the database. We're going to
  create a users table to hold all our users.



  24.5.  Step1: Creating the Users Table

  Start up database server and login to database.  Let's create the user
  table:


  ______________________________________________________________________
  psql> CREATE TABLE users (
  ->   username     char(16) not null,
  ->   password     char(32) not null,
  ->   priv         char(5) not null,
  ->   firstname    varchar(64) not null,
  ->   lastname     varchar(64) not null,
  ->   email        varchar(128) not null,
  ->   phone        varchar(32) not null,
  ->   address      varchar(255) not null,
  ->   PRIMARY KEY (username),
  ->   UNIQUE email (email)
  -> );
  ______________________________________________________________________


  Notice the constraints we've put on the users table, the username is
  the primary key (which makes sense, you should be able to identify a
  user record based on the username). The email address has a unique
  constraint as well because we don't want duplicate email addresses.

  Now let's add a record to create the root user with the password
  password:


  ______________________________________________________________________
  psql> INSERT INTO users VALUES (
  ->    'root',
  ->    '5f4dcc3b5aa765d61d8327deb882cf99',
  ->    'admin',
  ->    'System',
  ->    'Administrator',
  ->    'root@mymarket.com',
  ->    '555-5555',
  ->    '123 5 Avenue'
  -> );
  ______________________________________________________________________



  Notice the password looks a bit wierd,
  5f4dcc3b5aa765d61d8327deb882cf99. This is the MD5 hash of the the word
  "password", I won't go into details here, but the important thing to
  note is that it's a one-way algorithm and it always produces a 32
  character string.

  That's it, we have a users table to track our users, and one
  administrative account so we can try logging in and out of the system
  using the example tar file (download the example tar file from
  <http://www.devshed.com/Server_Side/PHP/Commerce1> ).



  25.  PHP Training & PHP Help Desk

  To obtain hands on training and to attend PHP courses:


  ·  PHP Training - 5 day hands on courses
     <http://www.tapinternet.com/php>



  ·  PHP Help Desk - 'as needed' live support (phone/email/chat), code
     audits for performance and security, and more. Visit
     <http://www.phphelpdesk.com>



  26.  Related URLs

  Visit following locators which are related to C, C++ -

  ·  Vim color text editor for C++, C
     <http://metalab.unc.edu/LDP/HOWTO/Vim-HOWTO.html>

  ·  SQL database server for PHP PostgreSQL
     <http://www.geocities.com/alavoor/HOWTO/pgsql/PostgreSQL-
     HOWTO.html> at pgsql-howto
     <http://www.geocities.com/alavoor/HOWTO/pgsql/PostgreSQL-
     HOWTO.html>

  ·  Source code control system CVS HOWTO for C++ programs
     <http://metalab.unc.edu/LDP/HOWTO/CVS-HOWTO.html>

  ·   Linux goodies main site is at  <http://24.221.230.253> and
     secondary site at  <http://www.milkywaygalaxy.freeservers.com>
     Mirror sites are at - angelfire
     <http://www.angelfire.com/country/aldev0>, geocities
     <http://www.geocities.com/alavoor/index.html>, virtualave
     <http://aldev0.virtualave.net>, Fortunecity
     <http://members.fortunecity.com/aldev>, Freewebsites
     <http://aldev.freewebsites.com>, Tripod
     <http://members.tripod.lycos.com/aldev>, 101xs
     <http://www.101xs.com/101xs/aldev>, 50megs
     <http://aldev0.50megs.com>,



  27.  Other Formats of this Document

  This document is published in 14 different formats namely - DVI,
  Postscript, Latex, Adobe Acrobat PDF, LyX, GNU-info, HTML, RTF(Rich
  Text Format), Plain-text, UNIX man pages, single HTML file, SGML
  (Linuxdoc format), SGML (Docbook format), MS WinHelp format.

  This howto document is located at -

  ·  <http://www.linuxdoc.org> and click on HOWTOs and search for howto
     document name using CTRL+f or ALT+f within the web-browser.

  You can also find this document at the following mirrors sites -

  ·  <http://www.caldera.com/LDP/HOWTO>

  ·  <http://www.linux.ucla.edu/LDP>

  ·  <http://www.cc.gatech.edu/linux/LDP>

  ·  <http://www.redhat.com/mirrors/LDP>

  ·  Other mirror sites near you (network-address-wise) can be found at
     <http://www.linuxdoc.org/mirrors.html> select a site and go to
     directory /LDP/HOWTO/xxxxx-HOWTO.html



  ·  You can get this HOWTO document as a single file tar ball in HTML,
     DVI, Postscript or SGML formats from -
     <ftp://www.linuxdoc.org/pub/Linux/docs/HOWTO/other-formats/> and
     <http://www.linuxdoc.org/docs.html#howto>


  ·  Plain text format is in:
     <ftp://www.linuxdoc.org/pub/Linux/docs/HOWTO> and
     <http://www.linuxdoc.org/docs.html#howto>


  ·  Single HTML file format is in:
     <http://www.linuxdoc.org/docs.html#howto>

     Single HTML file can be created with command (see man sgml2html) -
     sgml2html -split 0   xxxxhowto.sgml


  ·  Translations to other languages like French, German, Spanish,
     Chinese, Japanese are in
     <ftp://www.linuxdoc.org/pub/Linux/docs/HOWTO> and
     <http://www.linuxdoc.org/docs.html#howto> Any help from you to
     translate to other languages is welcome.

     The document is written using a tool called "SGML-Tools" which can
     be got from - <http://www.sgmltools.org> Compiling the source you
     will get the following commands like

  ·  sgml2html xxxxhowto.sgml     (to generate html file)

  ·  sgml2html -split 0   xxxxhowto.sgml (to generate a single page html
     file)

  ·  sgml2rtf  xxxxhowto.sgml     (to generate RTF file)

  ·  sgml2latex xxxxhowto.sgml    (to generate latex file)



  27.1.  Acrobat PDF format

  PDF file can be generated from postscript file using either acrobat
  distill or Ghostscript.  And postscript file is generated from DVI
  which in turn is generated from LaTex file.  You can download distill
  software from  <http://www.adobe.com>. Given below is a sample
  session:

  ______________________________________________________________________
  bash$ man sgml2latex
  bash$ sgml2latex filename.sgml
  bash$ man dvips
  bash$ dvips -o filename.ps filename.dvi
  bash$ distill filename.ps
  bash$ man ghostscript
  bash$ man ps2pdf
  bash$ ps2pdf input.ps output.pdf
  bash$ acroread output.pdf &
  ______________________________________________________________________


  Or you can use Ghostscript command ps2pdf.  ps2pdf is a work-alike for
  nearly all the functionality of Adobe's Acrobat Distiller product: it
  converts PostScript files to Portable Document Format (PDF) files.
  ps2pdf is implemented as a very small command script (batch file) that
  invokes Ghostscript, selecting a special "output device" called
  pdfwrite. In order to use ps2pdf, the pdfwrite device must be included
  in the makefile when Ghostscript was compiled; see the documentation
  on building Ghostscript for details.



  27.2.  Convert Linuxdoc to Docbook format

  This document is written in linuxdoc SGML format. The Docbook SGML
  format supercedes the linuxdoc format and has lot more features than
  linuxdoc.  The linuxdoc is very simple and is easy to use. To convert
  linuxdoc SGML file to Docbook SGML use the program ld2db.sh and some
  PERL scripts.  The ld2db output is not 100% clean and you need to use
  the clean_ld2db.pl PERL script. You may need to manually correct few
  lines in the document.

  ·  Download ld2db program from
     <http://www.dcs.gla.ac.uk/~rrt/docbook.html> or from Milkyway
     Galaxy site <http://www.milkywaygalaxy.freeservers.com>

  ·  Download the cleanup_ld2db.pl PERL script from from Milkyway Galaxy
     site <http://www.milkywaygalaxy.freeservers.com>

     The ld2db.sh is not 100% clean, you will get lots of errors when
     you run
     ___________________________________________________________________
             bash$ ld2db.sh file-linuxdoc.sgml db.sgml
             bash$ cleanup.pl db.sgml > db_clean.sgml
             bash$ gvim db_clean.sgml
             bash$ docbook2html db.sgml
     ___________________________________________________________________


  And you may have to manually edit some of the minor errors after run­
  ning the PERL script. For e.g. you may need to put closing tag <
  /Para> for each < Listitem>



  27.3.  Convert to MS WinHelp format

  You can convert the SGML howto document to Microsoft Windows Help
  file, first convert the sgml to html using:

  ______________________________________________________________________
          bash$ sgml2html xxxxhowto.sgml     (to generate html file)
          bash$ sgml2html -split 0   xxxxhowto.sgml (to generate a single page html file)
  ______________________________________________________________________


  Then use the tool HtmlToHlp <http://javadocs.planetmirror.com/html­
  tohlpe.html>.  You can also use sgml2rtf and then use the RTF files
  for generating winhelp files.



  27.4.  Reading various formats

  In order to view the document in dvi format, use the xdvi program. The
  xdvi program is located in tetex-xdvi*.rpm package in Redhat Linux
  which can be located through ControlPanel | Applications | Publishing
  | TeX menu buttons.  To read dvi document give the command -


               xdvi -geometry 80x90 howto.dvi
               man xdvi



  And resize the window with mouse.  To navigate use Arrow keys, Page
  Up, Page Down keys, also you can use 'f', 'd', 'u', 'c', 'l', 'r',
  'p', 'n' letter keys to move up, down, center, next page, previous
  page etc.  To turn off expert menu press 'x'.

  You can read postscript file using the program 'gv' (ghostview) or The
  ghostscript program is in ghostscript*.rpm package and gv program is
  in gv*.rpm package in Redhat Linux which can be located through
  ControlPanel | Applications | Graphics menu buttons. The gv program is
  much more user friendly than ghostscript.  Also ghostscript and gv are
  available on other platforms like OS/2, Windows 95 and NT, you view
  this document even on those platforms.


  ·  Get ghostscript for Windows 95, OS/2, and for all OSes from
     <http://www.cs.wisc.edu/~ghost>

  To read postscript document give the command -

                  gv howto.ps
                  ghostscript howto.ps



  You can read HTML format document using Netscape Navigator, Microsoft
  Internet explorer, Redhat Baron Web browser or any of the 10 other web
  browsers.

  You can read the latex, LyX output using LyX a X-Windows front end to
  latex.



  28.  Copyright

  Copyright policy is GNU/GPL as per LDP (Linux Documentation project).
  LDP is a GNU/GPL project.  Additional requests are - Please retain the
  author's name, email address and this copyright notice on all the
  copies. If you make any changes or additions to this document then you
  please intimate all the authors of this document.



  29.  Appendix A PHP examples

  29.1.  PostgreSQL large object Example

  Submitted by: PHP code exchange px@sklar.com To get this file, in the
  web-browser, save this file as 'Text' type as pgsql_largeobj.lib

  ______________________________________________________________________

  PX: PHP Code Exchange -
  <url name="PostgreSQL" url="http://www.geocities.com/alavoor/HOWTO/pgsql/PostgreSQL-HOWTO.html">
  large object access

  <?
          $database = pg_Connect ( "",  "",  "",  "",  "jacarta");
          pg_exec ($database,  "BEGIN");
          $oid = pg_locreate ($database);
          echo ( "$oid\n");
          $handle = pg_loopen ($database, $oid,  "w");
          echo ( "$handle\n");
          pg_lowrite ($handle,  "foo");
          pg_loclose ($handle);
          pg_exec ($database,  "COMMIT");
          pg_close ($database);
  ?>
  ______________________________________________________________________



  29.2.  User authentication Example

  To get this file, in the web-browser, save this file as 'Text' type as
  user_pw.lib

  From the PHP 3 Manual: Works only if PHP is an Apache module.  Instead
  of simply printing out the $PHP_AUTH_USER and $PHP_AUTH_PW, you would
  probably want to check the username and password for validity. Perhaps
  by sending a query to a database, or by looking up the user in a dbm
  file.


  ______________________________________________________________________
  <?php
          if (!$PHP_AUTH_USER)
          {
                  Header("WWW-authenticate: basic realm=\"My Realm\"");
                  Header("HTTP/1.0 401 Unauthorized");
                  echo "Text to send if user hits Cancel button\n";
                  exit;
          }
          else
          {
                  echo "Hello $PHP_AUTH_USER.<P>";
                  echo "You entered $PHP_AUTH_PW as your password.<P>";
          }
  ?>
  ______________________________________________________________________



  29.3.  Network admin Example

  To get this file, in the web-browser, save this file as 'Text' type as
  network.lib

  PHP: network adminstrator's best friend from
  <http://www.phpWizard.net>

  As a web-developer, you're probably used to such lovely tools as ping,
  whois, nslookup etc. But what when you need one of those utilities at
  a client's office and have no access to telnet? Good guess. Time to
  look up the functions in the "Network" section of the PHP manual.

  Socket operations:

  The most important function there is fsockopen(). Using this function,
  you can connect to any open port on a server and establish a socket
  connection with it. The function's syntax is as following:

  ______________________________________________________________________
          int fsockopen(string hostname, int port, int [errno], string [errstr]);
  ______________________________________________________________________


  The first two arguments are obvious, the next two are optional and
  used for error handling. The "errno" and "errstr" should be passed by
  reference.  "Passing by reference" means that the original variable
  will get modified. Normally, the content of a variable passed to a
  function wouldn't be modified.

  So, you could use this function to open a connection to a webserver
  and print out the headers:



  ______________________________________________________________________
  function get_headers($host, $path = "/")
  {
          $fp = fsockopen ("$host", 80, &$errnr, &$errstr) or die("$errno: $errstr");
          fputs($fp,"GET $path HTTP/1.0\n\n");
          while (!$end)
          {
                  $line = fgets($fp, 2048);
                  if (trim($line) == "")
                          $end = true;
                  else
                          echo $line;
          }
          fclose($fp);
  }
  ______________________________________________________________________


  In this example you see that you can apply any file operations (fread,
  fwrite etc) to the the pointer you got using the fsockopen() call.
  Note that the example realizes a HTTP/1.0 client - it won't work with
  name-based virtual hosts.

  Finger: Naturally, you can also open connections to other ports.
  Writing a small finger client with PHP is trivial therefore. Let's
  change the example from above to query a finger daemon:

  ______________________________________________________________________
  function finger ($host, $user)
  {
          $fp = fsockopen($host, 79, &$errno, &$errstr) or die("$errno: $errstr");
          fputs($fp, "$user\n");
          while (!feof($fp))
                  echo fgets($fp, 128);
          fclose($fp);
  }
  ______________________________________________________________________



  Whois: Querying a whois server uses the same concept:

  ______________________________________________________________________
  // domain is like "phpwizard.net"
  function whois($domain, $server="whois.internic.net")
  {
          $fp = fsockopen ($server, 43, &$errnr, &$errstr) or die("$errno: $errstr");
          fputs($fp, "$domain\n");
          while (!feof($fp))
                  echo fgets($fp, 2048);
          fclose($fp);
  }
  ______________________________________________________________________



  Blocking and non-blocking operations: But there's a problem with all
  those functions. They work fine if

  1. You have a connection with low latency and

  2. If the server you're connecting to is up and running.

     If not, your script will be busy until it times out. The reason for
     this is that default socket connections are blocking and don't time
     out. You can avoid these "hanging scripts" by switching to non-
     blocking socket operations. The function set_socket_blocking() does
     just that: it set all operations on a socket (first parameter:
     socket pointer) to either blocking (second parameter: true) or
     false (second parameter: false). Using non-blocking operations, the
     finger function would like like this:


  ______________________________________________________________________
          $fp = fsockopen($host, 79, &$errno, &$errstr) or die("$errno: [ ] $errstr");
          set_socket_blocking($fp, 0);
          fputs($fp, "$user\n");

          $stop = time() + $timeout;
          while (!feof($fp) && time() < $stop )
                  echo fgets($fp, 128);
          fclose($fp);
  ______________________________________________________________________


  Modifying these 3 functions to use non-blocking socket calls is left
  as an exercise for you.



  30.  Appendix B Midgard Installation

  RPMs for Midgard from <http://www.midgard-
  project.org/download/binaries> currently do not include PostgreSQL
  <http://www.geocities.com/alavoor/HOWTO/pgsql/PostgreSQL-HOWTO.html> ,
  and hence you need to install from the source tar ball file .

  Download the Midgard source tarball and read the INSTALL.REDHAT file -



  ______________________________________________________________________
  bash# cd midgard-lib-1.4beta6
  bash# ./configure --prefix=/usr/local --with-mysql=/usr/local --includedir=/usr/include/mysql --with-midgard=/usr/local --with-pgsql=/var/lib/pgsql --includedir=/usr/include/pgsql
  bash# make
  bash# make install
  bash# ldconfig -v | grep -i midga
  Copy the header files, just in case make install did not do that..
  bash# cp *.h /usr/local/include


  bash# cd ../mod_midgard-1.4beta5c
  bash# ./configure --prefix=/usr/local --with-mysql=/usr/local --includedir=/usr/include/mysql --with-midgard=/usr --with-pgsql=/var/lib/pgsql --includedir=/usr/include/pgsql
  bash# make
  bash# make install
  #modify apache line to correct /usr/.....
  bash# vi /etc/httpd/conf/httpd.conf   (or it is /etc/apache/httpd.conf)
  bash# /etc/init.d/apache restart
  #apache should restart!!!


  bash# cd ../midgard-php-1.4beta6
  bash# ./configure '--with-apxs' '--with-mysql' '--with-pgsql' '--with-midgard' --prefix=/usr/local --with-midgard=/usr/local

  bash# gvim Makefile
  And add -I/usr/include/pgsql to INCLUDE variable.

  Also add $(INCLUDE) to $(APXS) command as below -
  libphp3.so: mod_php3.c libmodphp3-so.a  pcrelib/libpcre.a midgard/libphpmidgard.a
          -@test -f ./mod_php3.c || test -L ./mod_php3.c || $(LN_S) $(srcdir)/mod_php3.c ./mod_php3.c
          -@test -f ./mod_php3.c || test -h ./mod_php3.c || $(LN_S) $(srcdir)/mod_php3.c ./mod_php3.c
          $(APXS) -c -o libphp3.so  -I$(srcdir) $(INCLUDE) -I. -I/usr/local/include -I/usr/lib/glib/include  -Wl,'-rpath /usr/local/lib' ./mod_php3.c libmodphp3-so.a $(APXS_LDFLAGS)

  bash# make
  bash# make install
  #modify apache line to correct /usr/.....
  # and add lines like these -
          LoadModule php4_module        modules/libphp4.so
          AddModule mod_php4.c
          LoadModule php4_module        lib/apache/libphp4.so

          <IfModule mod_php4.c>
                  AddType application/x-httpd-php4 .php4
                  AddType application/x-httpd-php4 .php
                  AddType application/x-httpd-php4-source .phps
                  AddType application/x-httpd-php .php
          </IfModule>

  bash# vi /etc/httpd/conf/httpd.conf   (or it is /etc/apache/httpd.conf)

  bash# /etc/init.d/apache restart
  #apache should restart!!!
  ______________________________________________________________________



  30.1.  Testing Midgard PHP Server

  To test the installation do this - Create a file in your document root
  directory.  I usually call it info.php and in it put this single line:



  ______________________________________________________________________
  <?phpinfo()?>
  ______________________________________________________________________



  Then load it up in your browser: http://localhost/info.php

  You should see a nice summary page showing all sorts of information
  about your setup.  You probably shouldn't leave this file around on a
  production server, but for debugging and general info during
  development, it is very handy.



  30.2.  Security OpenSSL

  You may also need to get the RSA package for to enable SSL encryption
  from <ftp://ftp.deva.net/pub/sources/crypto/rsaref20.1996.tar.Z> See
  also OpenSSL RPM package on Linux cdrom ( <http://www.openssl.org>

  If you do not want the SSL to be enabled (or if you face any problem),
  then download the source RPM of Apache-Midgard and edit the *.spec
  file and comment out SSL and rebuild the RPM.



  31.  Appendix C - Debug tool phpcodesite



  ______________________________________________________________________
  <
  ?php
  /*  phpCodeSite (Idea from CodeSite - Raize Software)
  *  @version 0.1b - 20001125
  *  @author Sébastien Hordeaux - <
  marms@marms.com>
  *  @licence GNU Public Licence
  *  Main site : http://phpcodesite.phpedit.com
  */

  /*
  ** How does it work ?
          Place a CS_EnterMethod() at the beginning of each method/function
          Place a CS_ExitMethod() at the beginning of each method/function
          Use CS_SendError() to log an error message
          Use CS_SendNote() to log a simple note message
          Use CS_SendMessage() to log a message
          To log variables: CS_SendVar & CS_SendArray()
          To see input data (global PHP variables) use CS_SendInputData()
  */


  if(defined("FLAG_PHPCODESITE_PHP")) return FALSE;
          define("FLAG_PHPCODESITE_PHP", 1);

  //  Start without increment
  $CS_Step = 0;

  CS_SetEnabled(TRUE);
  // CS_SetEnabled(FALSE);

  //  Switch between Enable/Disable mode
  function CS_SetEnabled($state){
          global $CS_Enabled;
          $CS_Enabled = $state;
          CS_Write($CS_Enabled?"<
          pre>":"<
          /pre>");
  }

  //  Add a level to the reported items
  function CS_IncStep(){
          global $CS_Step;
          $CS_Step++;
  }

  // Remove a level to the reported items
  function CS_DecStep(){
          global $CS_Step;
          $CS_Step--;
          if($CS_Step <
          0)
                  $CS_Step = 0;
  }

  // Log an item
  function CS_Log($msg){
          global $CS_Step;
          for($i = 0; $i <
          $CS_Step; $i++)
                  CS_WriteIndent();
          CS_Write($msg);
  }

  // Write data to the target output
  function CS_Write($str){
          global $CS_Enabled;
          if($CS_Enabled)
                  echo "$str";
  }

  // Write an indent block
  function CS_WriteIndent(){
          CS_Write("|   ");
  }

  // Beginning a new method
  function CS_EnterMethod($methodName){
          CS_Log("--> $methodName\n");
          CS_IncStep();
  }

  // Exit a method
  function CS_ExitMethod($methodName){
          CS_DecStep();
          CS_Log("<
          -- $methodName\n");
  }

  // Log a note
  function CS_SendNote($note){
          CS_Log("[O] $note\n");
  }

  // Send a simple message
  function CS_SendMessage($msg){
          CS_Log("[M] $msg\n");
  }

  // Log an error
  function CS_SendError($msg){
          CS_Log("<
          b>[E] $msg<
          /b>\n");
  }

  // Log a variable
  function CS_SendVar($varName, $value){
          if(is_array($value)){
                  CS_SendArray($value, $varName);
          }else{
                  CS_Log("[L] $varName = \"$value\"\n");
          }
  }

  // Write all global variables to the report
  function CS_SendInputData(){
          global $HTTP_GET_VARS, $HTTP_POST_VARS, $HTTP_COOKIE_VARS,
                  $HTTP_SERVER_VARS, $HTTP_ENV_VARS, $HTTP_SESSION_VARS;
          CS_Write("----------------------------------------------------------\n");
          CS_SendArray($HTTP_GET_VARS, "HTTP_GET_VARS");
          CS_SendArray($HTTP_POST_VARS, "HTTP_POST_VARS");
          CS_SendArray($HTTP_COOKIE_VARS, "HTTP_COOKIE_VARS");
          CS_SendArray($HTTP_SERVER_VARS, "HTTP_SERVER_VARS");
          CS_SendArray($HTTP_ENV_VARS, "HTTP_ENV_VARS");
          CS_SendArray($HTTP_SESSION_VARS, "HTTP_SESSION_VARS");
          CS_Write("----------------------------------------------------------\n");
  }

  // Log an array
  function CS_SendArray($array, $arrayStr = ""){
          if(!empty($arrayStr))
                  CS_Log("\$$arrayStr");
          if(count($array) == 0){
                  CS_Log(" = Array()\n");
          }else{
                  CS_Write(" = Array(\n");
                  while(list($key2, $value2) = each($array)){
                          CS_WriteIndent();
                          if(empty($arrayStr))
                          CS_WriteIndent();
                          CS_Log("$key2");
                          if(!is_array($value2))
                                  CS_Write(" => ".htmlentities($value2)."\n");
                          else
                                  CS_SendArray($value2);
                  }
                  CS_WriteIndent();
                  if(empty($arrayStr))
                          CS_WriteIndent();
                  CS_Log(")\n");
          }
  }
  ?>
  ______________________________________________________________________



  32.  Appendix D - PERL versus PHP debate

  PERL (Practical Extraction and Reporting Language) is kind of ancestor
  of PHP. PERL is immensely powerful and is in use for a very long time,
  just like "C" language. PERL can do everything that "C" language does.
  You are better off programming in PERL than in "C" language!!  Most of
  the "C" programmers prefer to program in PERL if speed is not that
  important (C programs is little faster than PERL).

  PERL5 is fully OOP operational.  Just because PERL can also do
  everything without OOP techniques does not mean it's not OOP.

  Comparing PERL to PHP, in terms of readability and scalability, they
  are nearly equal although PHP has a slight advantage for those who
  insist on using only client side code.  PERL is certainly easier to
  read than C due to it being a very high level language.  As you know,
  the biggest obstacle to multiple developer maintenance is compilers
  from which PERL does not suffer.

  PHP and PERL are equal in these ways:

  1. High level code.  English-like syntax is easy to read and logical

  2. Execution speed.  As raw interpreted source code, both are very
     fast (compared to VB and the like.)

  3. Ease and speed of development.  As scripts, both can be developed
     quickly bypassing the nasty compiler and with built-in intelligent
     debuggers.

  4. Run anywhere.  A dream these share which all other languages fail.

  5. Superior text processing to all other languages.

  6. Open source.

  7. Both are very well supported by whole Internet community

  8. Both are free.

  Where PHP has an advantage over PERL:

  1. Client-side code (for those who insist on such things.)

  2. Easier to compile into EXE.

  Where PERL might have an advantage over PHP.

  1. PERL is already installed on every web server in the world
     automatically during setup.

  2. PERL is more backward and forward compatible.

  3. PERL in all it's versions is VERY stable.

  4. PERL hooks into all existing dbase engines very easily.  The
     necessary modules come with every PERL distribution.  All that is
     required is up-to-date drivers which are easy to obtain.  PERL and
     MySQL are made for each other.



