CP Shrink - Revision history

Jsummers: /* File structure */

2025-07-30T15:04:02Z

‎File structure

Jsummers: /* Sample files */ Re-updated samples link

2025-07-30T15:01:45Z

‎Sample files: Re-updated samples link

Jsummers: Undo revision 46576 by Dexvertbot (talk)

2025-07-30T15:01:14Z

Undo revision 46576 by Dexvertbot (talk)

Dexvertbot: Change telparia.com samples link to template

2023-12-28T02:55:19Z

Change telparia.com samples link to template

Sembiance: /* Software */

2023-10-17T15:29:25Z

‎Software

Sembiance: Added sample files

2023-10-17T15:27:32Z

Added sample files

Jsummers at 17:19, 6 November 2021

2021-11-06T17:19:13Z

Jsummers at 18:35, 30 September 2021

2021-09-30T18:35:44Z

Jsummers: /* Software */

2021-09-30T18:15:42Z

‎Software

Jsummers: Created page with "{{FormatInfo |formattype=electronic |subcat=Archiving |extensions={{ext|cpz}} |released=≤1992 }} '''CP Shrink''' (or CPSHRINK) is a compressed archive program for DOS, and i..."

2021-09-29T17:19:01Z

Created page with "{{FormatInfo |formattype=electronic |subcat=Archiving |extensions={{ext|cpz}} |released=≤1992 }} '''CP Shrink''' (or CPSHRINK) is a compressed archive program for DOS, and i..."

New page

{{FormatInfo
|formattype=electronic
|subcat=Archiving
|extensions={{ext|cpz}}
|released=≤1992
}}
'''CP Shrink''' (or CPSHRINK) is a compressed archive program for DOS, and its native '''.CPZ''' file format. It was developed by Central Point Software. It usually uses [[PKWARE DCL Implode]] compression.

== Identification ==
There's no obvious way to identify a CPZ file from its contents. There is probably some sort of checksum field of that could be validated, but more research is needed.

== Software ==
* [{{SACFTPURL|pack|cpshrink.zip}} CP Shrink] (German language)

← Older revision		Revision as of 15:04, 30 July 2025
Line 10:		Line 10:

	CPSHRINK CPZ archive format overview		CPSHRINK CPZ archive format overview
		+	[Written for the fileformats.archiveteam.org wiki.]

	This information is based on reverse engineering. It may be incorrect		This information is based on reverse engineering. It may be incorrect

← Older revision		Revision as of 15:01, 30 July 2025
Line 71:		Line 71:

	== Sample files ==		== Sample files ==
−	* ~~https://telparia.com/fileFormatSamples/~~archive/cpShrink/	+	* {{DexvertSamples\|archive/cpShrink}}

@@ Line 23: / Line 23: @@
               8            Archive Header segment
               32×nmembers  Member File Headers segment
-32×nmembers               File Data area
++32×nmembers               File Data area
   Archive Header segment
@@ Line 44: / Line 44: @@
    Offset   Size   Description
    ------   ----   -----------
-       4      CRC of *compressed* file data
+  +0       4      CRC of *compressed* file data
-       15     Filename, NUL terminated
+  +4       15     Filename, NUL terminated
-      1      Compression method:
+  +19      1      Compression method:
 = [[PKWARE DCL Implode]], Binary
 = PKWARE DCL Implode, ASCII
 = not compressed
-      4      Original size
+  +20      4      Original size
-      4      Compressed size
+  +24      4      Compressed size
-      4      Timestamp ([[MS-DOS date/time|DOS date, time]])
+  +28      4      Timestamp ([[MS-DOS date/time|DOS date, time]])
   File Data area
-   The first file's compressed data starts at 8 32×nmembers.
+   The first file's compressed data starts at 8+32×nmembers.
    Location of other files' data is implied by the sum of the compressed
@@ Line 71: / Line 71: @@
 == Sample files ==
-* {{DexvertSamples|archive/cpShrink}}
+* https://telparia.com/fileFormatSamples/archive/cpShrink/

@@ Line 23: / Line 23: @@
               8            Archive Header segment
               32×nmembers  Member File Headers segment
-+32×nmembers               File Data area
+32×nmembers               File Data area
   Archive Header segment
@@ Line 44: / Line 44: @@
    Offset   Size   Description
    ------   ----   -----------
-  +0       4      CRC of *compressed* file data
+       4      CRC of *compressed* file data
-  +4       15     Filename, NUL terminated
+       15     Filename, NUL terminated
-  +19      1      Compression method:
+      1      Compression method:
 = [[PKWARE DCL Implode]], Binary
 = PKWARE DCL Implode, ASCII
 = not compressed
-  +20      4      Original size
+      4      Original size
-  +24      4      Compressed size
+      4      Compressed size
-  +28      4      Timestamp ([[MS-DOS date/time|DOS date, time]])
+      4      Timestamp ([[MS-DOS date/time|DOS date, time]])
   File Data area
-   The first file's compressed data starts at 8+32×nmembers.
+   The first file's compressed data starts at 8 32×nmembers.
    Location of other files' data is implied by the sum of the compressed
@@ Line 71: / Line 71: @@
 == Sample files ==
-* https://telparia.com/fileFormatSamples/archive/cpShrink/
+* {{DexvertSamples|archive/cpShrink}}

@@ Line 68: / Line 68: @@
 * [https://archive.org/details/PCToolsProV9.0German PC Tools Pro v9.0 (German)] → disk1.img → CPSHRINK.EXE (German)
 * [{{SACFTPURL|pack|cpshrink.zip}} CP Shrink], from the SAC collection (German)
 == Sample files ==
 * https://telparia.com/fileFormatSamples/archive/cpShrink/

← Older revision		Revision as of 15:27, 17 October 2023
Line 68:		Line 68:
	* [https://archive.org/details/PCToolsProV9.0German PC Tools Pro v9.0 (German)] → disk1.img → CPSHRINK.EXE (German)		* [https://archive.org/details/PCToolsProV9.0German PC Tools Pro v9.0 (German)] → disk1.img → CPSHRINK.EXE (German)
	* [{{SACFTPURL\|pack\|cpshrink.zip}} CP Shrink], from the SAC collection (German)		* [{{SACFTPURL\|pack\|cpshrink.zip}} CP Shrink], from the SAC collection (German)
		+
		+	== Sample files ==
		+	* https://telparia.com/fileFormatSamples/archive/cpShrink/

@@ Line 6: / Line 6: @@
 }}
 '''CP Shrink''' (or CPSHRINK) is a compressed archive program for DOS, and its native '''.CPZ''' file format. It was developed by Central Point Software. It usually uses [[PKWARE DCL Implode]] compression.
 == Identification ==
-There's no obvious way to identify a CPZ file from its contents. There is probably some sort of checksum field that could be validated, but more research is needed.
+There's no quick and easy way to identify a CPZ file from its contents. Validating the CRC of the file headers segment could work, but that segment does not have a fixed size.
 == Software ==

← Older revision		Revision as of 18:15, 30 September 2021
Line 11:		Line 11:

	== Software ==		== Software ==
−	* [{{SACFTPURL\|pack\|cpshrink.zip}} CP Shrink] (German ~~language~~)	+	* [https://archive.org/details/CentralPointMorePCTools2.0ForDOSAndWindows Central Point More PC Tools 2.0 for DOS and Windows (German)] → disk1.img → CPSHRINK.EXE (English)
		+	* [https://archive.org/details/PCToolsProV9.0German PC Tools Pro v9.0 (German)] → disk1.img → CPSHRINK.EXE (German)
		+	* [{{SACFTPURL\|pack\|cpshrink.zip}} CP Shrink], from the SAC collection (German)