MRNZ - Revision history

Sembiance: /* Sample files */

2024-09-19T19:24:16Z

‎Sample files

Jsummers at 18:27, 4 May 2024

2024-05-04T18:27:14Z

Jsummers: /* Identification */

2024-02-11T14:05:20Z

‎Identification

Jsummers: Created page with "{{FormatInfo |formattype=electronic |subcat=Archiving |extensions={{ext|??_}} |released=1994? }} '''MRNZ''' (for lack of a better name) is a simple installer-archive format. I..."

2024-02-11T12:44:14Z

Created page with "{{FormatInfo |formattype=electronic |subcat=Archiving |extensions={{ext|??_}} |released=1994? }} '''MRNZ''' (for lack of a better name) is a simple installer-archive format. I..."

New page

{{FormatInfo
|formattype=electronic
|subcat=Archiving
|extensions={{ext|??_}}
|released=1994?
}}
'''MRNZ''' (for lack of a better name) is a simple installer-archive format. It is a lightly obfuscated non-compressed single-file format. Its only known use is in certain distributions of IBM PC DOS 6.3, where it seems to be a companion to [[Microsoft KWAJ installation compression|KWAJ]] format.

== Format details ==
A file seems to be decoded as follows: Skip the first 12 bytes, [[Exclusive Or|xor]] the next 38 bytes with 0xAE, and copy the rest of the file unchanged.

== Identification ==
Files start with ASCII "{{magic|MRNZ}}", apparently always followed by {{magic|0x88 0xf0 0x27 0x33 0x26}}.

== Sample files ==
(Files here are likely in [[LoadDskF/SaveDskF]] disk images.)

* [https://archive.org/details/Shareware_Overload_Trio_Volume_2_Chestnut_CD-ROM Shareware Overload Trio Volume 2] → DIR41/USD631.*, ...
* [https://archive.org/details/os2_94 IBM Presents OS/2 Software Hits - First Edition 1994] → os2_94/I20/{FRD631.*, ..., GRD631.*, ...}

[[Category:Obfuscation]]
[[Category:IBM]]

@@ Line 21: / Line 21: @@
 * [https://archive.org/details/Shareware_Overload_Trio_Volume_2_Chestnut_CD-ROM Shareware Overload Trio Volume 2] → DIR41/USD631.*, ...
 * [https://archive.org/details/os2_94 IBM Presents OS/2 Software Hits - First Edition 1994] → os2_94/I20/{FRD631.*, ..., GRD631.*, ...}
 [[Category:Obfuscation]]
 [[Category:IBM]]

@@ Line 12: / Line 12: @@
 == Identification ==
 Files start with ASCII "{{magic|MRNZ}}", apparently always followed by {{magic|0x88 0xf0 0x27 0x33}}. The next four bytes always seem to be {{magic|0x26 0x00 0x00 0x00}}, but if this is the number of obfuscated bytes, it might be different for very small files.
 == Sample files ==