Difference between revisions of "Archiver"

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Barry Boone's utility '''ARCHIVER''' is the common tool to package files on the TI-99 and Geneve systems. Tim Tesch modified it for use with hard disks, in particular by changing the way the source directory is specified (you can provide a complete pathname).  
[[Barry Boone]]'s utility '''ARCHIVER''' is the common tool to package files on the TI-99 and Geneve systems. Tim Tesch modified it for use with hard disks, in particular by changing the way the source directory is specified (you can provide a complete pathname).
 
Bob's last version was 3.03, a complete rewrite of Version 2.  Files are compatible between versions and compressed/uncompressed files are handled transparently.
 
There is a View Text option.
 
Both variants - compressed and uncompressed - share the same data structures. The compressed variant is simply an LZW compression applied to the uncompressed archive file.
 
Introduced in Vn 3.03, Archiver now accepts drives 1-Z, for Ramdisk users.


== Uncompressed archive ==
== Uncompressed archive ==


Uncompressed archives contain the contents and metadata of a set of files in a single archive file. Uncompressed archives are stored in '''Dis/Fix 128''' format.
Uncompressed archives contain the contents and metadata of a set of files in a single archive file. Uncompressed archives are stored in '''Dis/Fix 128''' format.
When Uncompressed Archives are created, they are automatically write protected, since most Terminal Programs (modem programs) require that D/F 128 files be write protected either to work, or to transfer at an acceptable speed.


== Compressed archive ==
== Compressed archive ==
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Compressed archives are stored in '''Int/Fix 128''' format.
Compressed archives are stored in '''Int/Fix 128''' format.


Both variants - compressed and uncompressed - share the same data structures. The compressed variant is simply an LZW compression applied to the uncompressed archive file.
There are a very few kinds of files which cannot be compressed (attempting to compress them can actually make them LARGER! Known offenders are GIF pictures and Infocom games. Both of these kind of files are already compressed, in fact, GIF pictures use the same compression technique Archiver III uses! Which brings me to the next point: don't bother trying to compress a file twice... it'll just get larger the second time.
 
==Geneve compatability==
Version 3.0 or 3.01, are very unreliable on [[Geneve]], 3.02 has been "fixed" to be compatible with MDOS.
 
==Utilities==
The Load FW command is a loader for the [[Funnelweb]] program, and the Filename it looks for is UTIL1
 
[[Category:Software]] [[Category:File Format]]

Latest revision as of 13:36, 28 May 2016

Barry Boone's utility ARCHIVER is the common tool to package files on the TI-99 and Geneve systems. Tim Tesch modified it for use with hard disks, in particular by changing the way the source directory is specified (you can provide a complete pathname).

Bob's last version was 3.03, a complete rewrite of Version 2. Files are compatible between versions and compressed/uncompressed files are handled transparently.

There is a View Text option.

Both variants - compressed and uncompressed - share the same data structures. The compressed variant is simply an LZW compression applied to the uncompressed archive file.

Introduced in Vn 3.03, Archiver now accepts drives 1-Z, for Ramdisk users.

Uncompressed archive

Uncompressed archives contain the contents and metadata of a set of files in a single archive file. Uncompressed archives are stored in Dis/Fix 128 format.

When Uncompressed Archives are created, they are automatically write protected, since most Terminal Programs (modem programs) require that D/F 128 files be write protected either to work, or to transfer at an acceptable speed.

Compressed archive

The archive file may be compressed to save space on the storage medium. The compression used in ARCHIVER is Lempel-Ziv-Welch, also known as LZW. The implementation uses a variable bit count, starting with 9 bits, then increasing up to 12 bits. When all entries are used up, it restarts with 9 bits.

Compressed archives are stored in Int/Fix 128 format.

There are a very few kinds of files which cannot be compressed (attempting to compress them can actually make them LARGER! Known offenders are GIF pictures and Infocom games. Both of these kind of files are already compressed, in fact, GIF pictures use the same compression technique Archiver III uses! Which brings me to the next point: don't bother trying to compress a file twice... it'll just get larger the second time.

Geneve compatability

Version 3.0 or 3.01, are very unreliable on Geneve, 3.02 has been "fixed" to be compatible with MDOS.

Utilities

The Load FW command is a loader for the Funnelweb program, and the Filename it looks for is UTIL1