yet another compress question - VMS

This is a discussion on yet another compress question - VMS ; Hi, I'm hoping someone can help me... I need to decompress some files which where compressed using a program called 'compress' which we were running on a vax/vms system in the early 90's. Unfortunately we no longer have a fax ...

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  1. yet another compress question

    Hi,

    I'm hoping someone can help me...
    I need to decompress some files which where compressed using a program
    called 'compress' which we were running on a vax/vms system in the
    early 90's.
    Unfortunately we no longer have a fax and I'm unable to find any
    program which will decompress the files.
    Looking into the files shows the first two bytes as 1F 9E whereas 1F
    9D seems to be common for the compression utils I've found so far.

    Does anyone know of anything which can decompress these files
    (preferably running under dos but linux would be ok too.

    Thanks
    Paul

  2. Re: yet another compress question

    In article
    <909ac93b-fc4f-466c-a61b-94cc752d058a@n1g2000prb.googlegroups.com>,
    parnold@bellfruitgames.co.uk wrote:

    > Hi,
    >
    > I'm hoping someone can help me...
    > I need to decompress some files which where compressed using a program
    > called 'compress' which we were running on a vax/vms system in the
    > early 90's.
    > Unfortunately we no longer have a fax and I'm unable to find any
    > program which will decompress the files.
    > Looking into the files shows the first two bytes as 1F 9E whereas 1F
    > 9D seems to be common for the compression utils I've found so far.
    >
    > Does anyone know of anything which can decompress these files
    > (preferably running under dos but linux would be ok too.
    >
    > Thanks
    > Paul


    Have you had a look at this one?

    http://mvb.saic.com/freeware/freewarev40/compress_vms/

    --
    Paul Sture

    Sue's OpenVMS bookmarks:
    http://eisner.encompasserve.org/~stu...bookmarks.html

  3. Re: yet another compress question

    On Apr 7, 3:07*pm, "P. Sture" wrote:
    > In article
    > <909ac93b-fc4f-466c-a61b-94cc752d0...@n1g2000prb.googlegroups.com>,
    >
    >
    >
    >
    >
    > *parn...@bellfruitgames.co.uk wrote:
    > > Hi,

    >
    > > I'm hoping someone can help me...
    > > I need to decompress some files which where compressed using a program
    > > called 'compress' which we were running on a vax/vms system in the
    > > early 90's.
    > > Unfortunately we no longer have a fax and I'm unable to find any
    > > program which will decompress the files.
    > > Looking into the files shows the first two bytes as 1F 9E whereas 1F
    > > 9D seems to be common for the compression utils I've found so far.

    >
    > > Does anyone know of anything which can decompress these files
    > > (preferably running under dos but linux would be ok too.

    >
    > > Thanks
    > > Paul

    >
    > Have you had a look at this one?
    >
    > http://mvb.saic.com/freeware/freewarev40/compress_vms/
    >
    > --
    > Paul Sture


    Yes, unfortunately it expects the first 2 "magic bytes" to be 1F 9D

    Paul

  4. Re: yet another compress question

    parnold@bellfruitgames.co.uk wrote:
    > On Apr 7, 3:07 pm, "P. Sture" wrote:
    >> Have you had a look at this one?
    >>
    >> http://mvb.saic.com/freeware/freewarev40/compress_vms/

    >
    > Yes, unfortunately it expects the first 2 "magic bytes" to be 1F 9D


    If compress/zcompress/unix compress is not it, then lzcmp & lzdcmp could
    be an option.

    It is 12-15 years since I have last seen one of those, but it can
    still be found.

    http://mvb.saic.com/freeware/94bvmslt/tools/

    has both that and other tools.

    Arne

  5. Re: yet another compress question

    Thanks to everyone for their replies.

    I'm making some kind of progress but not there yet.
    The 1f 9e means it contains vms private data.

    Things are made more difficult by the fact that I don't have a vax so
    can't run any original code and all source code I've found doesn't
    compile on a pc without a lot of modification.

    Regards
    Paul

  6. Re: yet another compress question

    On Tue, 08 Apr 2008 04:31:37 -0700, wrote:

    > Thanks to everyone for their replies.
    >
    > I'm making some kind of progress but not there yet.
    > The 1f 9e means it contains vms private data.
    >
    > Things are made more difficult by the fact that I don't have a vax so
    > can't run any original code and all source code I've found doesn't
    > compile on a pc without a lot of modification.


    What is the source written in?

    Ask someone with a VAX to run it. Just for kicks did you try changing the
    'e'
    to 'd' ?

    >
    > Regards
    > Paul




    --
    PL/I for OpenVMS
    www.kednos.com

  7. Re: yet another compress question

    The source is written in C but there is some vms specific stuff to do
    with vms descriptors etc.
    Also, my compiler doesn't like the function declarations, the style is
    generally :
    function( var1, var 2 )
    char var1
    int char2
    etc

    Changing the 9E to 9D doesn't work as the 9E adds some additional info
    and changes the initialisation of the decompressor slightly.

    I don't know anyone with a vax but if anyone on here would be kind
    enough to try decompressing a file for me I'm more than happy to send
    it.
    I have about 20 files in total but if I could get one done it'd be a
    starting point.

    Thanks
    Paul


  8. Re: yet another compress question

    On Tue, 08 Apr 2008 05:39:07 -0700, wrote:

    > The source is written in C but there is some vms specific stuff to do
    > with vms descriptors etc.
    > Also, my compiler doesn't like the function declarations, the style is
    > generally :
    > function( var1, var 2 )
    > char var1
    > int char2
    > etc
    >
    > Changing the 9E to 9D doesn't work as the 9E adds some additional info
    > and changes the initialisation of the decompressor slightly.
    >
    > I don't know anyone with a vax but if anyone on here would be kind
    > enough to try decompressing a file for me I'm more than happy to send
    > it.
    > I have about 20 files in total but if I could get one done it'd be a
    > starting point.
    >
    > Thanks
    > Paul
    >

    So me the program you want to use to decompress and a file and I will try


    --
    PL/I for OpenVMS
    www.kednos.com

  9. Re: yet another compress question

    parnold@bellfruitgames.co.uk wrote:
    > The source is written in C but there is some vms specific stuff to do
    > with vms descriptors etc.
    > Also, my compiler doesn't like the function declarations, the style is
    > generally :
    > function( var1, var 2 )
    > char var1
    > int char2
    > etc
    >
    > Changing the 9E to 9D doesn't work as the 9E adds some additional info
    > and changes the initialisation of the decompressor slightly.
    >
    > I don't know anyone with a vax but if anyone on here would be kind
    > enough to try decompressing a file for me I'm more than happy to send
    > it.
    > I have about 20 files in total but if I could get one done it'd be a
    > starting point.
    >
    > Thanks
    > Paul
    >


    There's a commercial service in New York that specializes in recovering
    data from weird media or damaged media. They MAY also be able to deal
    with strange compression schemes.

    Muller Media Conversions
    21 Locust Street
    Manhasset, NY 11030
    http://www.mullermedia.com/

    1-516-833-3067

    For the price of an envelope and a stamp or a phone call, you can find
    out if they can help. Tell Chris I sent you.

  10. Re: yet another compress question

    On Apr 8, 2:42*pm, "Richard B. Gilbert"
    wrote:

    > There's a commercial service in New York that specializes in recovering
    > data from weird media or damaged media. *They MAY also be able to deal
    > with strange compression schemes.
    >


    Thanks for the info Richard.

    I have made some progress. The compression is lzw with a few bytes at
    the beginning of the file which aren't compressed.
    There are some additional control codes for end-of-record and other
    stuff.
    Not got far though because it only decompresses upto the point where
    lzw changes to 10 bits and then it produces garbage so I only get
    about 300 bytes of valid data
    At least there's a glimmer of hope.

    Paul

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