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Classes | Public Types | Static Public Member Functions | List of all members
G::File Class Reference

A simple static class for dealing with files. More...

`#include <gfile.h>`

## Classes
class | Append
| An overload discriminator for G::File::open(). More...
struct | CreateExclusive
| An overload discriminator for G::File::open(). More...
struct | Stat
| A portable 'struct stat'. More...
class | Text
| An overload discriminator for G::File::open(). More...

## Public Types
enum class | InOut { In , Out }
enum class | InOutAppend { In , Out , Append , OutNoCreate }
enum class | Seek { Start , Current , End }

## Static Public Member Functions
static bool | remove (const Path &path, std::nothrow_t) noexcept
| Deletes the file or directory. Returns false on error. More...
static void | remove (const Path &path)
| Deletes the file or directory. Throws an exception on error. More...
static bool | cleanup (const Cleanup::Arg &path_arg) noexcept
| Deletes the file. More...
static bool | rename (const Path &from, const Path &to, std::nothrow_t) noexcept
| Renames the file. More...
static void | rename (const Path &from, const Path &to, bool ignore_missing=false)
| Renames the file. More...
static bool | renameOnto (const Path &from, const Path &to, std::nothrow_t) noexcept
| Renames the file, deleting 'to' first if necessary. More...
static bool | copy (const Path &from, const Path &to, std::nothrow_t)
| Copies a file. Returns false on error. More...
static void | copy (const Path &from, const Path &to)
| Copies a file. More...
static void | copy (std::istream &from, std::ostream &to, std::streamsize limit=0U, std::size_t block=0U)
| Copies a stream with an optional size limit. More...
static Path | backup (const Path &from, std::nothrow_t)
| Creates a backup copy of the given file in the same directory and with a lightly-mangled filename. More...
static bool | copyInto (const Path &from, const Path &to_dir, std::nothrow_t)
| Copies a file into a directory and does a chmodx() if necessary. More...
static bool | mkdirs (const Path &dir, std::nothrow_t, int=100)
| Creates a directory and all necessary parents. More...
static void | mkdirs (const Path &dir, int=100)
| Creates a directory and all necessary parents. More...
static bool | mkdir (const Path &dir, std::nothrow_t)
| Creates a directory. More...
static void | mkdir (const Path &dir)
| Creates a directory. More...
static bool | isEmpty (const Path &file, std::nothrow_t)
| Returns true if the file size is zero. More...
static std::string | sizeString (const Path &file)
| Returns the file's size in string format. More...
static bool | exists (const Path &file)
| Returns true if the file (directory, device etc.) exists. More...
static bool | exists (const Path &file, std::nothrow_t)
| Returns true if the file (directory, device etc.) exists. More...
static bool | isExecutable (const Path &, std::nothrow_t)
| Returns true if the path is probably executable by the calling process. More...
static bool | isLink (const Path &path, std::nothrow_t)
| Returns true if the path is an existing symlink. More...
static bool | isDirectory (const Path &path, std::nothrow_t)
| Returns true if the path exists() and is a directory. More...
static Stat | stat (const Path &path, bool symlink_nofollow=false)
| Returns a file status structure. More...
static SystemTime | time (const Path &file)
| Returns the file's timestamp. Throws on error. More...
static SystemTime | time (const Path &file, std::nothrow_t)
| Returns the file's timestamp. More...
static void | chmodx (const Path &file)
| Makes the file executable. Throws on error. More...
static bool | chmodx (const Path &file, std::nothrow_t)
| Makes the file executable. More...
static void | chmod (const Path &file, const std::string &spec)
| Sets the file permissions. More...
static void | chgrp (const Path &file, const std::string &group)
| Sets the file group ownership. Throws on error. More...
static bool | chgrp (const Path &file, const std::string &group, std::nothrow_t)
| Sets the file group ownership. Returns false on error. More...
static bool | chgrp (const Path &file, gid_t group_id, std::nothrow_t)
| Sets the file group ownership. Returns false on error. More...
static G::Path | readlink (const Path &link)
| Reads a symlink. Throws on error. More...
static G::Path | readlink (const Path &link, std::nothrow_t)
| Reads a symlink. Returns the empty path on error. More...
static void | link (const Path &target, const Path &new_link)
| Creates a symlink. More...
static bool | link (const Path &target, const Path &new_link, std::nothrow_t)
| Creates a symlink. Returns false on error. More...
static bool | hardlink (const Path &src, const Path &dst, std::nothrow_t)
| Creates a hard link. More...
static void | create (const Path &)
| Creates the file if it does not exist. More...
static int | compare (const Path &, const Path &, bool ignore_whitespace=false)
| Compares the contents of the two files. Returns 0, 1 or -1. More...
static void | open (std::ofstream &, const Path &)
| Calls open() on the given output file stream. More...
static void | open (std::ofstream &, const Path &, Append)
| Calls open() on the given output file stream. More...
static void | open (std::ofstream &, const Path &, Text)
| Calls open() on the given output file stream. More...
static void | open (std::ifstream &, const Path &)
| Calls open() on the given input file stream. More...
static void | open (std::ifstream &, const Path &, Text)
| Calls open() on the given input file stream. More...
static std::filebuf * | open (std::filebuf &, const Path &, InOut)
| Calls open() on the given filebuf. More...
static int | open (const Path &, InOutAppend, bool windows_inherit=false) noexcept
| Opens a file descriptor. More...
static int | open (const Path &, CreateExclusive) noexcept
| Creates a file and returns a writable file descriptor. More...
static std::FILE * | fopen (const Path &, const char *mode) noexcept
| Calls std::fopen(). More...
static bool | probe (const Path &) noexcept
| Creates and deletes a temporary probe file. More...
static ssize_t | read (int fd, char *, std::size_t) noexcept
| Calls read() or equivalent. More...
static ssize_t | write (int fd, const char *, std::size_t) noexcept
| Calls ::write() or equivalent. More...
static void | close (int fd) noexcept
| Calls ::close() or equivalent. More...
static std::streamoff | seek (int fd, std::streamoff offset, Seek) noexcept
| Does ::lseek() or equivalent. More...
static void | setNonBlocking (int fd) noexcept
| Sets the file descriptor to non-blocking mode. More...
static bool | remove (const char *, std::nothrow_t)=delete
static bool | remove (const std::string &, std::nothrow_t)=delete
static bool | rename (const char *, const Path &, std::nothrow_t)=delete
static bool | rename (const std::string &, const Path &, std::nothrow_t)=delete
static bool | rename (const char *, const char *, std::nothrow_t)=delete
static bool | rename (const std::string &, const std::string &, std::nothrow_t)=delete
static bool | renameOnto (const char *, const char *, std::nothrow_t)=delete
static bool | renameOnto (const std::string &, const std::string &, std::nothrow_t)=delete
static int | open (const char *, InOutAppend)=delete
static int | open (const std::string &, InOutAppend)=delete
static int | open (const char *, CreateExclusive)=delete
static int | open (const std::string &, CreateExclusive)=delete
static std::FILE * | fopen (const char *, const char *mode)=delete
static std::FILE * | fopen (const std::string &, const char *mode)=delete
static bool | probe (const char *)=delete
static bool | probe (const std::string &)=delete

## Detailed Description

A simple static class for dealing with files.

See also
  G::Path, G::FileSystem, G::Directory

Definition at line 43 of file gfile.h.

## Member Enumeration Documentation

## ◆ InOut

enum class G::File::InOut
| strong

Definition at line 58 of file gfile.h.

## ◆ InOutAppend

enum class G::File::InOutAppend
| strong

Definition at line 59 of file gfile.h.

## ◆ Seek

enum class G::File::Seek
| strong

Definition at line 60 of file gfile.h.

## Member Function Documentation

## ◆ backup()

G::Path G::File::backup | ( | const Path & | from,
|  | std::nothrow_t |
| ) |  |
| static

Creates a backup copy of the given file in the same directory and with a lightly-mangled filename.

Sets a tight umask. Returns the path of the backup file or the empty path on error.

Definition at line 322 of file gfile.cpp.

## ◆ chgrp() [1/3]

void G::File::chgrp | ( | const Path & | file,
|  | const std::string & | group
| ) |  |
| static

Sets the file group ownership. Throws on error.

Definition at line 370 of file gfile_unix.cpp.

## ◆ chgrp() [2/3]

bool G::File::chgrp | ( | const Path & | file,
|  | const std::string & | group,
|  | std::nothrow_t |
| ) |  |
| static

Sets the file group ownership. Returns false on error.

Definition at line 379 of file gfile_unix.cpp.

## ◆ chgrp() [3/3]

bool G::File::chgrp | ( | const Path & | file,
|  | gid_t | group_id,
|  | std::nothrow_t |
| ) |  |
| static

Sets the file group ownership. Returns false on error.

Definition at line 385 of file gfile_unix.cpp.

## ◆ chmod()

void G::File::chmod | ( | const Path & | file,
|  | const std::string & | spec
| ) |  |
| static

Sets the file permissions.

Throws on error. The spec is a simplified sub-set of the /bin/chmod command syntax. The umask is ignored.

Definition at line 272 of file gfile_unix.cpp.

## ◆ chmodx() [1/2]

void G::File::chmodx | ( | const Path & | file | ) |
| static

Makes the file executable. Throws on error.

Definition at line 229 of file gfile.cpp.

## ◆ chmodx() [2/2]

bool G::File::chmodx | ( | const Path & | file,
|  | std::nothrow_t |
| ) |  |
| static

Makes the file executable.

Definition at line 223 of file gfile.cpp.

## ◆ cleanup()

bool G::File::cleanup | ( | const Cleanup::Arg & | path_arg | ) |
| static noexcept

Deletes the file.

Returns false on error. Used in G::Cleanup handlers:

Definition at line 172 of file gfile_unix.cpp.

## ◆ close()

void G::File::close | ( | int | fd | ) |
| static noexcept

Calls ::close() or equivalent.

Definition at line 159 of file gfile_unix.cpp.

## ◆ compare()

int G::File::compare | ( | const Path & | path_1,
|  | const Path & | path_2,
|  | bool | ignore_whitespace = `false`
| ) |  |
| static

Compares the contents of the two files. Returns 0, 1 or -1.

Definition at line 293 of file gfile.cpp.

## ◆ copy() [1/3]

void G::File::copy | ( | const Path & | from,
|  | const Path & | to
| ) |  |
| static

Copies a file.

Definition at line 59 of file gfile.cpp.

## ◆ copy() [2/3]

bool G::File::copy | ( | const Path & | from,
|  | const Path & | to,
|  | std::nothrow_t |
| ) |  |
| static

Copies a file. Returns false on error.

Definition at line 67 of file gfile.cpp.

## ◆ copy() [3/3]

void G::File::copy | ( | std::istream & | from,
|  | std::ostream & | to,
|  | std::streamsize | limit = `0U`,
|  | std::size_t | block = `0U`
| ) |  |
| static

Copies a stream with an optional size limit.

Definition at line 110 of file gfile.cpp.

## ◆ copyInto()

bool G::File::copyInto | ( | const Path & | from,
|  | const Path & | to_dir,
|  | std::nothrow_t |
| ) |  |
| static

Copies a file into a directory and does a chmodx() if necessary.

Returns false on error.

Definition at line 73 of file gfile.cpp.

## ◆ create()

void G::File::create | ( | const Path & | path | ) |
| static

Creates the file if it does not exist.

Leaves it alone if it does. Throws on error.

Definition at line 135 of file gfile_unix.cpp.

## ◆ exists() [1/2]

bool G::File::exists | ( | const Path & | file | ) |
| static

Returns true if the file (directory, device etc.) exists.

Symlinks are followed. Throws an exception if permission denied or too many symlinks etc.

Definition at line 136 of file gfile.cpp.

## ◆ exists() [2/2]

bool G::File::exists | ( | const Path & | file,
|  | std::nothrow_t |
| ) |  |
| static

Returns true if the file (directory, device etc.) exists.

Symlinks are followed. Returns false on error.

Definition at line 141 of file gfile.cpp.

## ◆ fopen()

std::FILE * G::File::fopen | ( | const Path & | path,
|  | const char * | mode
| ) |  |
| static noexcept

Calls std::fopen().

Definition at line 114 of file gfile_unix.cpp.

## ◆ hardlink()

bool G::File::hardlink | ( | const Path & | src,
|  | const Path & | dst,
|  | std::nothrow_t |
| ) |  |
| static

Creates a hard link.

Returns false on error or if not implemented.

Definition at line 390 of file gfile_unix.cpp.

## ◆ isDirectory()

bool G::File::isDirectory | ( | const Path & | path,
|  | std::nothrow_t |
| ) |  |
| static

Returns true if the path exists() and is a directory.

Symlinks are followed. Returns false on error.

Definition at line 179 of file gfile.cpp.

## ◆ isEmpty()

bool G::File::isEmpty | ( | const Path & | file,
|  | std::nothrow_t |
| ) |  |
| static

Returns true if the file size is zero.

Returns false on error.

Definition at line 192 of file gfile.cpp.

## ◆ isExecutable()

bool G::File::isExecutable | ( | const Path & | path,
|  | std::nothrow_t |
| ) |  |
| static

Returns true if the path is probably executable by the calling process.

Because of portability and implementation difficulties this does not return a definitive result so it should only used for generating warnings on a false return. Returns false on error.

Definition at line 185 of file gfile.cpp.

## ◆ isLink()

bool G::File::isLink | ( | const Path & | path,
|  | std::nothrow_t |
| ) |  |
| static

Returns true if the path is an existing symlink.

Returns false on error.

Definition at line 167 of file gfile.cpp.

## ◆ link() [1/2]

void G::File::link | ( | const Path & | target,
|  | const Path & | new_link
| ) |  |
| static

Creates a symlink.

If the link already exists but is not not pointing at the correct target then the link is deleted and recreated. Throws on error.

Definition at line 396 of file gfile_unix.cpp.

## ◆ link() [2/2]

bool G::File::link | ( | const Path & | target,
|  | const Path & | new_link,
|  | std::nothrow_t |
| ) |  |
| static

Creates a symlink. Returns false on error.

Definition at line 416 of file gfile_unix.cpp.

## ◆ mkdir() [1/2]

void G::File::mkdir | ( | const Path & | dir | ) |
| static

Creates a directory.

Throws on error (including EEXIST).

Definition at line 241 of file gfile.cpp.

## ◆ mkdir() [2/2]

bool G::File::mkdir | ( | const Path & | dir,
|  | std::nothrow_t |
| ) |  |
| static

Creates a directory.

Returns false on error (including EEXIST).

Definition at line 235 of file gfile.cpp.

## ◆ mkdirs() [1/2]

void G::File::mkdirs | ( | const Path & | dir,
|  | int | limit = `100`
| ) |  |
| static

Creates a directory and all necessary parents.

Throws on error, but EEXIST is not an error.

Definition at line 284 of file gfile.cpp.

## ◆ mkdirs() [2/2]

bool G::File::mkdirs | ( | const Path & | dir,
|  | std::nothrow_t | ,
|  | int | limit = `100`
| ) |  |
| static

Creates a directory and all necessary parents.

Returns false on error, but EEXIST is not an error and chmod errors are also ignored.

Note that the EEXIST result is ignored even if the target path already exists as a non-directory. This is a feature not a bug because it can avoid races.

Definition at line 276 of file gfile.cpp.

## ◆ open() [1/8]

int G::File::open | ( | const Path & | path,
|  | CreateExclusive |
| ) |  |
| static noexcept

Creates a file and returns a writable file descriptor.

Fails if the file already exists. Returns -1 on error. Uses SH_DENYNO and O_BINARY on windows.

Definition at line 106 of file gfile_unix.cpp.

## ◆ open() [2/8]

int G::File::open | ( | const Path & | path,
|  | InOutAppend | mode,
|  | bool | windows_inherit = `false`
| ) |  |
| static noexcept

Opens a file descriptor.

Returns -1 on error. Uses SH_DENYNO, O_BINARY and optionally O_NOINHERIT on windows. The inherit flag is ignored on unix.

Definition at line 91 of file gfile_unix.cpp.

## ◆ open() [3/8]

std::filebuf * G::File::open | ( | std::filebuf & | fb,
|  | const Path & | path,
|  | InOut | inout
| ) |  |
| static

Calls open() on the given filebuf.

Returns the address of the given filebuf, or nullptr on failure. Uses SH_DENYNO and O_BINARY on windows.

Definition at line 83 of file gfile_unix.cpp.

## ◆ open() [4/8]

void G::File::open | ( | std::ifstream & | ifstream,
|  | const Path & | path
| ) |  |
| static

Calls open() on the given input file stream.

Uses SH_DENYNO and O_BINARY on windows.

Definition at line 71 of file gfile_unix.cpp.

## ◆ open() [5/8]

void G::File::open | ( | std::ifstream & | ifstream,
|  | const Path & | path,
|  | Text |
| ) |  |
| static

Calls open() on the given input file stream.

This overload is for native end-of-line conversion. Uses SH_DENYNO and O_BINARY on windows.

Definition at line 77 of file gfile_unix.cpp.

## ◆ open() [6/8]

void G::File::open | ( | std::ofstream & | ofstream,
|  | const Path & | path
| ) |  |
| static

Calls open() on the given output file stream.

Uses SH_DENYNO and O_BINARY on windows.

Definition at line 56 of file gfile_unix.cpp.

## ◆ open() [7/8]

void G::File::open | ( | std::ofstream & | ofstream,
|  | const Path & | path,
|  | Append |
| ) |  |
| static

Calls open() on the given output file stream.

This overload is for append-on-every-write mode. Uses SH_DENYNO and O_BINARY on windows.

Definition at line 66 of file gfile_unix.cpp.

## ◆ open() [8/8]

void G::File::open | ( | std::ofstream & | ofstream,
|  | const Path & | path,
|  | Text |
| ) |  |
| static

Calls open() on the given output file stream.

This overload is for native end-of-line conversion. Uses SH_DENYNO and O_BINARY on windows.

Definition at line 61 of file gfile_unix.cpp.

## ◆ probe()

bool G::File::probe | ( | const Path & | path | ) |
| static noexcept

Creates and deletes a temporary probe file.

Fails if the file already exists. Returns false on error.

Definition at line 120 of file gfile_unix.cpp.

## ◆ read()

ssize_t G::File::read | ( | int | fd,
|  | char * | p,
|  | std::size_t | n
| ) |  |
| static noexcept

Calls read() or equivalent.

Definition at line 149 of file gfile_unix.cpp.

## ◆ readlink() [1/2]

G::Path G::File::readlink | ( | const Path & | link | ) |
| static

Reads a symlink. Throws on error.

Definition at line 436 of file gfile_unix.cpp.

## ◆ readlink() [2/2]

G::Path G::File::readlink | ( | const Path & | link,
|  | std::nothrow_t |
| ) |  |
| static

Reads a symlink. Returns the empty path on error.

Definition at line 445 of file gfile_unix.cpp.

## ◆ remove() [1/2]

void G::File::remove | ( | const Path & | path | ) |
| static

Deletes the file or directory. Throws an exception on error.

Definition at line 183 of file gfile_unix.cpp.

## ◆ remove() [2/2]

bool G::File::remove | ( | const Path & | path,
|  | std::nothrow_t |
| ) |  |
| static noexcept

Deletes the file or directory. Returns false on error.

Definition at line 177 of file gfile_unix.cpp.

## ◆ rename() [1/2]

void G::File::rename | ( | const Path & | from,
|  | const Path & | to,
|  | bool | ignore_missing = `false`
| ) |  |
| static

Renames the file.

Throws on error, but optionally ignores errors caused by a missing 'from' file or missing 'to' directory component.

Definition at line 46 of file gfile.cpp.

## ◆ rename() [2/2]

bool G::File::rename | ( | const Path & | from,
|  | const Path & | to,
|  | std::nothrow_t |
| ) |  |
| static noexcept

Renames the file.

Whether it fails if 'to' already exists depends on the o/s (see also renameOnto()). Returns false on error.

Definition at line 40 of file gfile.cpp.

## ◆ renameOnto()

bool G::File::renameOnto | ( | const Path & | from,
|  | const Path & | to,
|  | std::nothrow_t |
| ) |  |
| static noexcept

Renames the file, deleting 'to' first if necessary.

Returns false on error.

Definition at line 144 of file gfile_unix.cpp.

## ◆ seek()

std::streamoff G::File::seek | ( | int | fd,
|  | std::streamoff | offset,
|  | Seek | origin
| ) |  |
| static noexcept

Does ::lseek() or equivalent.

Definition at line 472 of file gfile_unix.cpp.

## ◆ setNonBlocking()

void G::File::setNonBlocking | ( | int | fd | ) |
| static noexcept

Sets the file descriptor to non-blocking mode.

Definition at line 480 of file gfile_unix.cpp.

## ◆ sizeString()

std::string G::File::sizeString | ( | const Path & | file | ) |
| static

Returns the file's size in string format.

Returns the empty string on error.

Definition at line 199 of file gfile.cpp.

## ◆ stat()

G::File::Stat G::File::stat | ( | const Path & | path,
|  | bool | symlink_nofollow = `false`
| ) |  |
| static

Returns a file status structure.

Returns with the 'error' field set on error. The 'symlink_nofollow' parameter value is ignored on Windows.

Definition at line 174 of file gfile.cpp.

## ◆ time() [1/2]

G::SystemTime G::File::time | ( | const Path & | file | ) |
| static

Returns the file's timestamp. Throws on error.

Definition at line 205 of file gfile.cpp.

## ◆ time() [2/2]

G::SystemTime G::File::time | ( | const Path & | file,
|  | std::nothrow_t |
| ) |  |
| static

Returns the file's timestamp.

Returns SystemTime(0) on error.

Definition at line 214 of file gfile.cpp.

## ◆ write()

ssize_t G::File::write | ( | int | fd,
|  | const char * | p,
|  | std::size_t | n
| ) |  |
| static noexcept

Calls ::write() or equivalent.

Definition at line 154 of file gfile_unix.cpp.

The documentation for this class was generated from the following files:

- /tmp/slackdce/slackrepo.HKsbdz/build_emailrelay/emailrelay-2.6/src/glib/gfile.h
- /tmp/slackdce/slackrepo.HKsbdz/build_emailrelay/emailrelay-2.6/src/glib/gfile.cpp
- /tmp/slackdce/slackrepo.HKsbdz/build_emailrelay/emailrelay-2.6/src/glib/gfile_unix.cpp
- /tmp/slackdce/slackrepo.HKsbdz/build_emailrelay/emailrelay-2.6/src/glib/gfile_win32.cpp