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diff --git a/doc/alf14_doc.txt b/doc/alf14_doc.txt deleted file mode 100644 index 832f59d..0000000 --- a/doc/alf14_doc.txt +++ /dev/null @@ -1,266 +0,0 @@ - AlfCrunch Documentation Revised 7/10/88 - ----------------------- - - AlfCrunch is an implementation of the Lempel-Ziv compression - algorithm. Although it produces files that have the same structure as - those produced by the Arc program, the two are not compatible. Arc - cannot uncrunch AlfCrunch files, nor can AlfUnCrunch unarc normal Arc - files. - - The current version of the LZ/DZ files is 1.4. Versions 1.1 through 1.3 - are compatible, but not with 1.0. If you have 1.0, you should discard it - and use 1.4. The reason for this is that 1.0 used the same header as - normal Arc crunch. Because of possible confusion over this, the header - used by AlfCrunch was changed. Since 1.0 had very limited distribution, - this situation should not often arise. For those who wish to be able to - detect the AlfCrunch format, the first two bytes of the file will always - be $1A $0F. - - This version fixes an annoying bug in both v1.2 and 1.3. If you had a -subdirectory entry amongst the filenames you were crunching, LZ would -stop at the subdir entry. Also the stack errors will now cause a proper -exit to Dos rather than re-execution. - - Enhancements to v1.4 are the addition of time/date support. If you -are running under Sparta 3.2, LZ will store the Sparta date/time from each -file into the header. DZ does not use this information, it's just there to -provide a reference point. - - When running either LZ.COM or DZ.COM, Memlo must be under $3000. This - should not normally be a problem unless you have a lot of handlers -installed. - A cartridge may be present, as it only affects the size of the buffer - available to AlfCrunch. Maximum speed will be achieved without a - cartridge being present. - - A final note - ------------ - - Well I think this is about as far as AlfCrunch is going to get for now. I -don't really believe there are any more features to add without modifying the -command line parameters. So this version (1.4) will be the last for -some time to come. Except for bug fixes (few if any I hope) the 1.x line will -not change. I hope to add command line parameters similar to ARC and maybe -add the ARC compression methods to finally resolve the compatibility issue. - - Alfred - Programmer's Aid BBS - (416) 465-4182 - - Running AlfCrunch - ----------------- - - To crunch files, load LZ.COM. The title will be displayed, along - with the version which should be 1.4. You will then be prompted for - the output filename. This may be up to 80 characters long, - including subdirectory names. - - If the output file already exists, it is checked to see if it is an -AlfCrunch file. If the first header is correct, then the new files will be -appended to it. If the header is wrong the program will print an error -message and exit to Dos. If the file is shorter than the header length -(29 bytes), then it is simply opened for normal output, which erases it. - - Next you will be prompted for the input filemask. This is what will - be used to select the files. This may also be up to 80 characters long, - including any subdirectory names. Wildcards are allowed. If selecting - all files, the mask must end in *.* . - - Finally, you have the option of turning the screen off. Selecting - this option will speed up the program by 15-20%. Once selected, you will - not again be prompted for this option. If you do not elect to turn the - screen off, the program will continue to present this prompt until it is - selected. - - The program will then select files using the mask and compress them, - displaying the filenames as it progresses. When it has finished, it will - prompt you for additional input filemasks. You may either enter another - mask or simply press return to exit back to Dos. - - LZ and SpartaDos 3.2 - -------------------- - - If you are using SpartaDos 3.2, you may invoke LZ.COM and specify - the output file and input filemask on the command line. The format is: - - [Dn:]LZ Dn:[path>]filename[.ext] [Dn:[path>]filename[.ext] ] - - The square brackets denote optional parameters which may be omitted. - The first filename is the output file. The second is the input - filemask. If you do not specify the input filemask, the program will - prompt you for it. The program will automatically turn the screen off. - When it is finished it will prompt you for more input filemasks. - - To invoke LZ as part of a batch file, the format is almost identical. - The lines in the batch file would be: - - [Dn:]LZ Dn:[path>]filename[.ext] [Dn:[path>]filename[.ext] ] - Dn:[path>]filename[.ext] <- Additional - Dn:[path>]filename[.ext] input masks - - The program will read each input filemask, compress the files - selected and continue until all the input masks have been used. You will - then be prompted for more input masks. If this is part of a larger batch - file, leave a single return after the last input mask to force LZ to - return control back to the batch file. Example: - - [Dn:]LZ Dn:[path>]filename[.ext] [Dn:[path>]filename[.ext] ] - Dn:[path>]filename[.ext] - Dn:[path>]filename[.ext] - (single return here) - [Dn:]LZ Dn:[path>]filename[.ext] [Dn:[path>]filename[.ext] ] - Dn:[path>]filename[.ext] - Dn:[path>]filename[.ext] - (single return here) - - At the end of this, you will be left at the Dos prompt. Because of - the way i/o redirection is handled, an alternative form is available: - - [Dn:]LZ - Dn:[path>]filename[.ext] <- The output file - Dn:[path>]filename[.ext] <- The input filemask - Y <- Turn the screen off - Dn:[path>]filename[.ext] <- Additional - Dn:[path>]filename[.ext] <- input filemasks - (single return here) - - Notice that the Y was only supplied once. When LZ is run in this - manner, it behaves exactly as if you were pressing the keys yourself. If - you turn the screen off, then you need only enter the Y once. If you - said N, then you would need an N after every input filemask until you - said Y. Example: - - [Dn:]LZ - Dn:[path>]filename[.ext] <- The output file - Dn:[path>]filename[.ext] <- The input filemask - N <- Leave the screen on - Dn:[path>]filename[.ext] <- Additional mask - N <- Leave the screen on - Dn:[path>]filename[.ext] <- Additional mask - Y <- Screen off now - Dn:[path>]filename[.ext] <- Additional masks, but no Y - Dn:[path>]filename[.ext] <- is necessary - (single return here) - - Getting Them Back - ----------------- - - To extract the files from an Alfcrunch file, load DZ.COM The title - will be displayed, along with the version number. - - The first prompt is for the name of the file to uncrunch. This - filename may be up to 80 characters long, including subdirectory names. - Wildcards are not allowed. - - The next prompt is the output directory. This is the directory where - the files will be placed when extracted from the crunch file. If the - directory does not exist, an attempt will be made to create the - directory. This may involve creating a number of subdirectories to get - to the last one, so care should exercised with this feature. If - errors occur during the directory build stage, an error message will be - displayed, and the program will return to DOS. You may specify a wildcard to -only extract certain files or use '*.*' to extract them all. *.* is the default. - - Auto directory creation is only available under SpartaDos. Under - any other Dos, if you specify a subdirectory, you will probably get -a single file with the name of the first pathname. - - Assuming all is well, you again have the option of turning the screen - off while files are being extracted. - - The program will then extract each file and place it in the output - directory specified. If any errors occur, an error message is printed - and the program returns to Dos. When all files have been extracted, you - will be prompted for another input file. You may enter another filename - or press Return to exit to Dos. - - The situation may arise where the crunch file has been corrupted. - This may occur due to errors during download, or failure of the disk on - which the file resides. There are several error messages which are - associated with bit errors. - - Msg: Not An AlfCrunch File! - --------------------------- - If this message is issued before any files were extracted, then - either the first two bytes of the file are corrupt, or else the file was - not created by AlfCrunch. If the message is issued after several files - were extracted, then the file has been damaged somewhere in the last - file extracted. You may also get the message which is described next. - - Msg: File Checksum In Error - --------------------------- - DZ has detected that the checksum calculated for the filename just - extracted does not agree with the checksum in the header block. Either - the header block has been damaged or more likely, the file itself has - been corrupted. If the file is a text file, it may be partially correct. - Object file types should be discarded, as it must be assumed they are - corrupt. - - Msg: Stack Overrun - ------------------ - This is an internal DZ error. The file being processed has been - corrupted, and DZ has exhausted all free memory in attempting to extract - the data. The output file produced is incomplete, corrupt, and should be - discarded. - - Msg: Extra Bytes At Eof, Don't Add To File - ------------------------------------------ - This means that the file has extra data at the end which is not valid. -This may arise from downloading where the last block is padded. Do not add -new files to it with LZ as you will not be able to get them back when you run -DZ again. You will get the 'Not An AlfCrunch File!' message at that time. - - DZ and SpartaDos 3.2 - -------------------- - If you are using SpartaDos 3.2, you may invoke DZ.COM and specify - the input file and output directory on the command line. The format is: - - [Dn:]DZ Dn:[path>]filename[.ext] [Dn:[path>][*.*] - - The square brackets denote optional parameters which may be omiited - if you wish. The first filename is the file to be processed. The second - filename is the directory in which the output files are to be placed. - Remember, if any of the directories in the output path do not exist, an - attempt will be made to create them. Remember, you can use a wildcard to -limit the files or take the default -which is '*.*'. - - The program will automatically turn the screen off, and extract - the files. If any errors occur, the appropriate error message will - be printed and control will return to Dos. - - When DZ is finished with the current input file, it will again prompt - you for another input file. You may continue uncrunching files, or - simply press return to exit back to Dos. - - As part of a batch file, the form for DZ is almost identical to the - LZ form. Accordingly, only brief examples will be shown: - - [Dn:]DZ Dn:[path>]filename[.ext] [Dn:[path>][*.*] - Dn:[path>]filename[.ext] <- Second input file - Dn:[path>][*.*] <- Second output path - Dn:[path>]filename[.ext] <- Third input file - Dn:[path>][*.*] <- Third output path - (single return) <- Return to Dos - - The second format is: - - [Dn:]DZ Dn:[path>]filename[.ext] <- First input file - Dn:[path>][*.*] <- First output path - Dn:[path>]filename[.ext] <- Second input file - Dn:[path>][*.*] <- Second output path - Dn:[path>]filename[.ext] <- Third input file - Dn:[path>][*.*] <- Third output path - (single return) <- Return to Dos - - The third format is: - - [Dn:]DZ - Dn:[path>]filename[.ext] <- First input file - Dn:[path>][*.*] <- First output path - Y <- Screen off - Dn:[path>]filename[.ext] <- Second input file - Dn:[path>][*.*] <- Second output path - Dn:[path>]filename[.ext] <- Third input file - Dn:[path>][*.*] <- Third output path - (single return) <- Exit to Dos |