ARJ for OS/2, version 2.75                           December, 31, 2000


   This product is an OS/2-hosted add-on for ARJ v 2.7x for DOS. It may be
   used  separately  from  the DOS  package  but  it doesn't  contain  the
   documentation found in DOS release.

   ***********************************************************************
   ***                                                                 ***
   ***  THIS PRODUCT IS DEVELOPED  SEPARATELY FROM THE MAINSTREAM ARJ  ***
   ***  PACKAGE AND  THEREFORE IS NOT  UPDATED SYNCHRONOUSLY WITH ARJ  ***
   ***  FOR DOS. SHAREWARE REGISTRATION FOR  ARJ/2 IS NOT PROVIDED BY  ***
   ***  ARJ SOFTWARE, INC.                                             ***
   ***                                                                 ***
   ***********************************************************************


   INTRODUCTION

      This file describes the features  specific to the OS/2 port. It is
      suggested that you read the general README file prior to this one.


   SYSTEM REQUIREMENTS

   16-bit version:

      *  OS/2 version 1.2 or higher, or Windows NT v 3.10 or higher.
   For OS/2 systems:
      *  A 80286 or higher CPU.
      *  512K of free memory
   For Windows NT systems:
      *  1024K of free memory

   32-bit version:

      *  OS/2 version 3.0 with Fixpak 26 or higher
      *  A 80386SX or higher CPU.
      *  1024K of free memory (512K for each subsequent  instance after
         the first one has been started)
      *  IBM LIBC and Unicode runtime  support (installed by default as
         a mandatory component)


   IMPLEMENTATION ISSUES

      *  External garble modules are provided as OS/2 DLLs. You may not
         use DOS  modules  with  ARJ/2, or vice  versa. The  encryption
         algorithm  is  the  same, so  ARJ/2 garbled  archives can   be
         processed under DOS.

      *  ARJ/2  sets  the  "Host OS" to  "OS/2"  on its  archives. When
         extracting  any such  archive with ARJ  for DOS,  some unusual
         behavior  may  occur. Versions  of ARJ  prior to 2.50  convert
         high-ASCII  characters in  filenames to  7-bit  characters  by
         ignoring the  high  bit. So, the  filename  "ąTESTą"  will  be
         converted to "1TEST1" on extraction.

         ARJ/DOS also strips high  bit from  archive comments, but only
         if the archive  was created  by ARJ/2. Archives  created  with
         ARJ/DOS  and  then  processed   under OS/2  are not  affected.

         Beginning  with version  2.72, ARJ/DOS considers  the ARJSFXJR
         archives created  under OS/2 to be hostile  to the DOS version
         of ARJSFXJR and  therefore cannot  modify them. In such cases,
         it's advised to use the "-2d" switch under OS/2.

      *  ARJ/2 uses the  default OS/2 error  handler that will normally
         display  pop-up menus  prompting  for action.  The  -&  option
         installs batch error and  exception handler (new feature since
         ARJ/2 v 2.62.08). Remember  that the  ampersand  character  is
         used  in OS/2 to start  two  processes  consequently, so  this
         switch will actually split  the command line. Type -^& instead
         of -& to install the error handler.

      *  ARJSFX and  ARJSFXJR archives  will display  ANSI sequences if
         the ANSI support is enabled in the  current OS/2 session (it's
         enabled by default in OS/2).

      *  By default, ARJ/2 stores extended attributes among with files.
         To  disable  EA  storage  and thus revert  to  the traditional
         header format, use  the "-2e" option. See  a special dedicated
         section below for details on EA handling.

      *  "-2p<n>" can  be  used  to  set  the  priority  of  ARJ/2. The
         knowledge  of OS/2 scheduling system  is required to  use this
         option. It can dramatically increase performance but slow down
         other processes. The <n> can be equal to 1, 2, 3 or 4:

          1 = idle-time priority
          2 = regular priority
          3 = time-critical priority
          4 = fixed-high priority

         Priority  delta  values  are not  supported.  We  don't see  a
         strong requirement for them.

      *  ARJSFXJR does  not  support  long filenames  under Win95  DOS.
         ARJSFXJR in ARJ/2 supports OS/2 long filenames.


   KNOWN PROBLEMS

      *  On FAT volumes under Windows NT, both long filenames and short
         filenames may be used to specify a filename. If you refer to a
         file  with its  short name (e.g. "ARJ a lntest LONGFI~1.TXT"),
         the short filename will be stored as entered from console. So,
         no LFN equivalent is placed  into the  archive, and if  a file
         with a  similar long  filename exists in the  archive, it will
         not be replaced.

      *  REARJ/2 may  behave incorrectly  if  the  command  interpreter
         (specified   with  COMSPEC=   environment  variable)  is   not
         compatible with CMD.EXE. It's also unwise to  rename REARJ.EXE
         since  it  calls itself recursively  when  converting archives
         within archives (/a).


      End of document