Squeeze - Revision history

Dexvertbot: /* Sample files */

2023-12-28T04:18:07Z

‎Sample files

Dexvertbot: /* Sample files */

2023-12-28T04:17:43Z

‎Sample files

JTN: fix rotted classiccmp.org links

2023-02-18T19:14:25Z

fix rotted classiccmp.org links

Jsummers: /* Tools */

2022-11-06T15:54:17Z

‎Tools

Sembiance: /* Sample files */

2022-03-15T22:38:12Z

‎Sample files

Jsummers: /* Tools */

2021-04-29T15:51:33Z

‎Tools

Jsummers: /* Disambiguation */

2021-01-10T17:18:36Z

‎Disambiguation

Jsummers: /* Format details */

2020-09-27T13:35:08Z

‎Format details

Jsummers at 13:23, 27 September 2020

2020-09-27T13:23:20Z

Jsummers: /* Specifications */ Squeeze's header is just not particularly to similar to Crunch and CRLZH

2020-09-20T19:32:02Z

‎Specifications: Squeeze's header is just not particularly to similar to Crunch and CRLZH

@@ Line 119: / Line 119: @@
 * [http://cpmarchives.classiccmp.org/cpm/mirrors/oak.oakland.edu/pub/cpm/ OAK CP/M archive] → .../*.?q?
 * Found in many [[LBR#Sample files|LBR]] files. Note that you may have to tell your LBR utility not to decompress them (e.g. <code>lbrate -n</code>).
-* {{DexvertSamples|squeeze}}
+* {{DexvertSamples|archive/squeeze}}
 == References ==

@@ Line 119: / Line 119: @@
 * [http://cpmarchives.classiccmp.org/cpm/mirrors/oak.oakland.edu/pub/cpm/ OAK CP/M archive] → .../*.?q?
 * Found in many [[LBR#Sample files|LBR]] files. Note that you may have to tell your LBR utility not to decompress them (e.g. <code>lbrate -n</code>).
-* https://telparia.com/fileFormatSamples/archive/squeeze/
+* {{DexvertSamples|squeeze}}
 == References ==

@@ Line 99: / Line 99: @@
 == Specifications ==
-* See the [http://www.classiccmp.org/cpmarchives/cpm/mirrors/oak.oakland.edu/pub/cpm/squsq/ SQUSQ] directory on CP/M archives for various source code and documentation (much of it, unfortunately, itself squeezed/crunched).
+* See the [http://cpmarchives.classiccmp.org/cpm/mirrors/oak.oakland.edu/pub/cpm/squsq/ SQUSQ] directory on CP/M archives for various source code and documentation (much of it, unfortunately, itself squeezed/crunched).
 * {{CdTextfiles|simtel/simtel/DISK1/DISC2/COMPRESS/SQDATE.DOC|SQDATE.DOC}} - Information about the timestamp extension
@@ Line 109: / Line 109: @@
 * {{Deark}}
 * On CP/M (or emulators):
-** The original tools were SQ/USQ. See for instance the [http://www.classiccmp.org/cpmarchives/cpm/mirrors/oak.oakland.edu/pub/cpm/squsq/ SQUSQ] directory of the Oakland CP/M archive.
+** The original tools were SQ/USQ. See for instance the [http://cpmarchives.classiccmp.org/cpm/mirrors/oak.oakland.edu/pub/cpm/squsq/ SQUSQ] directory of the Oakland CP/M archive.
-** The later LT31 deals with extracting from all of [[Squeeze]], [[Crunch]], [[CrLZH]] and [[LBR]] formats. Widely available in CP/M archives, e.g. [http://www.classiccmp.org/cpmarchives/cpm/mirrors/oak.oakland.edu/pub/cpm/arc-lbr/lt31.lbr LT31.LBR]
+** The later LT31 deals with extracting from all of [[Squeeze]], [[Crunch]], [[CrLZH]] and [[LBR]] formats. Widely available in CP/M archives, e.g. [http://cpmarchives.classiccmp.org/cpm/mirrors/oak.oakland.edu/pub/cpm/arc-lbr/lt31.lbr LT31.LBR]
-* [http://www.classiccmp.org/cpmarchives/cpm/mirrors/oak.oakland.edu/pub/cpm/squsq/squprt33.ark squprt33.ark] - Portable sq/usq, version "3.3 10/29/86"
+* [http://cpmarchives.classiccmp.org/cpm/mirrors/oak.oakland.edu/pub/cpm/squsq/squprt33.ark squprt33.ark] - Portable sq/usq, version "3.3 10/29/86"
 * {{CdTextfiles|carousel/013B/NSQUSQ.ZIP|NSQUSQ.ZIP}} - Contains NUSQ v1.10 (1984-10-21; By Dave Rand, Paul Homchick and Cliff Sharp) and NSQ v2.01 (1984-10-20; "Originally by Richard Greenlaw") (DOS Software)
 * {{CdTextfiles|simtel/simtel20/MSDOS/COMPRESS/SQPC131.ZIP|SQPC131.ZIP}} - SQPC v1.31 (1986-03-02) and UNSQPC v1.36, by Vernon D. Buerg (DOS Software)
@@ Line 117: / Line 117: @@
 == Sample files ==
-* [http://www.classiccmp.org/cpmarchives/ftp.php?b=cpm/mirrors/oak.oakland.edu/pub/cpm/ OAK CP/M archive] → .../*.?q?
+* [http://cpmarchives.classiccmp.org/cpm/mirrors/oak.oakland.edu/pub/cpm/ OAK CP/M archive] → .../*.?q?
 * Found in many [[LBR#Sample files|LBR]] files. Note that you may have to tell your LBR utility not to decompress them (e.g. <code>lbrate -n</code>).
 * https://telparia.com/fileFormatSamples/archive/squeeze/

@@ Line 107: / Line 107: @@
 * [http://www.svgalib.org/rus/lbrate.html lbrate] by Russell Marks, c. 2001 (Unix, GPL2)
 * [[The Unarchiver]]
 * On CP/M (or emulators):
 ** The original tools were SQ/USQ. See for instance the [http://www.classiccmp.org/cpmarchives/cpm/mirrors/oak.oakland.edu/pub/cpm/squsq/ SQUSQ] directory of the Oakland CP/M archive.

@@ Line 118: / Line 118: @@
 * [http://www.classiccmp.org/cpmarchives/ftp.php?b=cpm/mirrors/oak.oakland.edu/pub/cpm/ OAK CP/M archive] → .../*.?q?
 * Found in many [[LBR#Sample files|LBR]] files. Note that you may have to tell your LBR utility not to decompress them (e.g. <code>lbrate -n</code>).
 == References ==

@@ Line 18: / Line 18: @@
 * [[Squeeze It]] (SQZ) - A compression-and-archival format for DOS released around 1992.
 * [[SQUEEZE (AJP Systems)]] - A Windows 3.x file compression program and format.
 * Squeez [https://www.sac.sk/download/pack/squeez.zip] - A compression/archiving application for 32-bit Windows, with internal support for several standard formats. By Sven Ritter and SpeedProject.
 * Squeez, UnSqueez - Terms used for software and technology associated with [[SQX]] format, by Sven Ritter and SpeedProject.

@@ Line 33: / Line 33: @@
 == Format details ==
-Multi-byte integers are little-endian.
+Note:
 {| class="wikitable"
 ! Field !! Size in bytes !! Description
@@ Line 73: / Line 76: @@
 | 0 ... 255 || Pointer to a child node
 |}
 === Timestamp extension ===

@@ Line 2: / Line 2: @@
 |formattype=electronic
 |subcat=Compression
-|extensions={{ext|?q?}}, {{ext|qqq}}
+|extensions={{ext|?q?}}, {{ext|qqq}}, {{ext|sq}}
 |wikidata={{wikidata|Q34745668}}
 |released=ca. 1981
@@ Line 10: / Line 10: @@
 [[Squeeze]] was a method of compressing single files popular on [[CP/M]], devised by Richard Greenlaw circa 1981. It was superseded by [[Crunch]] and later [[CrLZH]]. Squeezed files were common in [[LBR]] archives. It uses [[Huffman coding]] combined with [[run-length encoding]].
-Squeezed files were signified in CP/M's 8.3 filename format by replacing the middle letter of the extension with Q (.?Q? -- so FOO.TXT became FOO.TQT), with the extension .QQQ used for corner cases such as a blank extension.
+Squeezed files were signified in CP/M's 8.3 filename format by replacing the middle letter of the extension with Q (.?Q? -- so FOO.TXT became FOO.TQT), with the extension .QQQ used for corner cases such as a blank extension. Some software for other platforms (e.g. squprt33.ark) appends a .SQ extension instead.
 The <tt>/usr/share/misc/magic</tt> file on Linux systems suggests that it was perhaps also in use on the [[Apple II|Apple ][]] platform, and in fact [[Binary II]] files are often found squeezed (as .bqy instead of .bny). Versions for PC/MS-DOS were also in use in the early 1980s before [[ARC (compression format)|ARC]] caught on as the dominant archiver.
@@ Line 42: / Line 42: @@
 |checksum || 2 || Low 16 bits of the sum of the decompressed byte values.
 |-
-|original filename || variable || Terminated by a NUL byte.
+|filename || variable || Original filename, terminated by a NUL byte. (TODO: Find a specification for this field. Some software interprets it in the same way as [[Crunch]], but that might be overkill.)
 |-
 |compressed data || variable || See below.
@@ Line 107: / Line 107: @@
 ** The original tools were SQ/USQ. See for instance the [http://www.classiccmp.org/cpmarchives/cpm/mirrors/oak.oakland.edu/pub/cpm/squsq/ SQUSQ] directory of the Oakland CP/M archive.
 ** The later LT31 deals with extracting from all of [[Squeeze]], [[Crunch]], [[CrLZH]] and [[LBR]] formats. Widely available in CP/M archives, e.g. [http://www.classiccmp.org/cpmarchives/cpm/mirrors/oak.oakland.edu/pub/cpm/arc-lbr/lt31.lbr LT31.LBR]
 * {{CdTextfiles|carousel/013B/NSQUSQ.ZIP|NSQUSQ.ZIP}} - Contains NUSQ v1.10 (1984-10-21; By Dave Rand, Paul Homchick and Cliff Sharp) and NSQ v2.01 (1984-10-20; "Originally by Richard Greenlaw") (DOS Software)
 * {{CdTextfiles|simtel/simtel20/MSDOS/COMPRESS/SQPC131.ZIP|SQPC131.ZIP}} - SQPC v1.31 (1986-03-02) and UNSQPC v1.36, by Vernon D. Buerg (DOS Software)