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 Some common formats in public domain
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To save diskspace and transfer  time,    most files in anonymous ftp server
are compressed in certain way. Here are some common compression format:

(1)ZIP format

This is the most common one for  PC.    You need  unzip utility to retrieve
files. The one that is provided in  ifcss.org is pkunzip.exe. pkunzip.exe is 
in software/dos/utils/ directory.  

There are also  zip/unzip  utilities  for  unix  and  vms systems. They are
available in software/unix/utils/ and software/vms/utils/  at  ifcss.org,
which are unz50p1.tar.Z and unzip.exe/unzip.readme respectively.  
You  can use them to unzip files on your mainframe machines.

(2)Unix Compressed files:

Unix compressed file has an  extension  '.Z'. For example, cnd-g archive in
ifcss.org  is  .Z  compressed.  Those   files    can  be  uncompressed  by
'uncompress' command on Unix. '.tar.Z'  is compressed unix tape archive. To
extract files from such an  archive  file, uncompress first, then untar the
'.tar' file. Example:
uncompress gb2ps.tar.Z
tar -xf gb2ps.tar

There are also unix compression  utilities  for vms system. compress.exe in
software/vms/utils directory is one of them.  So you can uncompress  a unix 
.Z file on a VMS system too.  vmstar in the same directory is for tar and 
untar files on vms system. 

The  compression/uncompression  utilities for dos system,  compress.exe and
uncompress.exe are in software/dos/utils directory. The tar.exe in the same 
directory is for tar/untar  utility on a PC/DOS machine.

(3)Compression on Mac:

Mac files in  anonymous  ftp  often  have  .sit  or  sit.hqx extensions. To
uncompress/unarchive these files, use StuffIt and Binhex. Details are given
in MacHelp in software/mac directory at ifcss.org.

(4)Other formats:

The other compression formats  often  seen  in  anonymous servers are .lzh,
.arc, .zoo. 

HXWZ uses extension .gb to  indicate  GB  coded  Chinese.  If a file has an
extension BIG or BIG5, it is BIG5 coded Chinese. 

GIF stands for Graphic Interchange Format. xxxx.gif's are pictures.  

All these compressed files such  as  .zip,  .Z, .lzh, .sit are binary ones.
They should be transferred in  binary  mode.  .gif and .exe are also binary
files. .hqx, uue, and .txt are  text  files.  They  should be transfered in 
ascii mode. 

