View source for DOC2COM (Gerald DePyper)

{{FormatInfo
|formattype=electronic
|subcat=Executable envelopes
|extensions={{ext|com}}
|released=1990
}}
'''DOC2COM''' is a DOS utility for creating a [[DOS executable (.com)|COM]] file that, when executed, displays a text document in a full-screen viewer. It was developed by Gerald (Jerry) DePyper.

When viewing a document, press F1 for help. Sometimes there is a function (Alt-F) to write the text to a file, but it depends on the DOC2COM version, and the options used when creating the file.

== Format details ==
Starting with v1.3, the embedded text is usually encrypted (obfuscated).

To de-obfuscate, XOR each obfuscated byte with the obfuscated byte following it, or with <code>0xff</code> for the very last byte.

== Identification ==
(To identify a generated file...)

'''Version 1990-04-03''': The first 16 bytes are:
 be 5e 04 b9 18 00 e8 b2 01 e2 fb 3b 36 54 04 72

'''Version 1990-12-01''': The first 16 bytes are:
 be 62 04 b9 18 00 e8 b2 01 e2 fb 3b 36 58 04 72

'''v1.2:''' The first 16 bytes are:
 fc be 50 0b b9 18 00 e8 2f 02 e2 fb 3b 36 46 0b

'''v1.3+:''' Files start with the byte pattern:
 fc ?? ?? ?? ?? 49 8b 36 ?? ?? 8b fe ac 32 04 aa
 e2 fa ac 34 ff aa ...

For v1.3+, the byte at offset 1 is <code>8b</code> if encrypted, or <code>eb</code> if not encrypted.

== Software ==
* DOC2COM
** Unversioned 1990-04-03 release: {{CdTextfiles|microhaus/mhblackbox3/FILEUTIL/DOC2COM.ZIP|DOC2COM.ZIP}}
** Unversioned 1990-12-01 release: {{CdTextfiles|nopv07/048A/DOC2CO.ZIP|DOC2CO.ZIP}}
** v1.2 (1991-04-14): {{CdTextfiles|swexplorer/disk1/A014/DOC2CM12.ZIP|DOC2CM12.ZIP}}
** v1.3[1992-06-27 release]: {{CdTextfiles|pier01/035a/doc2com3.zip|doc2com3.zip}}
** v1.3[1993-05-21 release]: {{CdTextfiles|swheaven3/WORDPROC/DOC2COM.ZIP|DOC2COM.ZIP}}
** v1.31 (1994-05-18): {{CdTextfiles|psl/pslv3nv04/UTILS/DOS/FILEVIEW/DOC2COM.ZIP|DOC2COM.ZIP}}
** v1.40 (1995-06-05): {{CdTextfiles|psl/pslv3nv08/DOS/UT_DSKFI/DOC2COM.ZIP|DOC2COM.ZIP}}

== Sample files ==
* {{CdTextfiles|swextrav1993/disk3/homepers/readut.zip|readut.zip}} → readme.com (1990-04-03)
* {{CdTextfiles|nightowl/nopv06/002A/BOLO1.ZIP|BOLO1.ZIP}} → README.COM (1990-12-01)
* {{CdTextfiles|swexplorer/disk1/A002/GREYHND.ZIP|GREYHND.ZIP}} → README.COM (v1.20)
* {{CdTextfiles|simtel/simtel0595/DISC1/ANIMATE/NBIRD20.ZIP|NBIRD20.ZIP}} README.COM (1.3x)
* {{CdTextfiles|nightowl/nopv18/049A/B2S10.ZIP|B2S10.ZIP}} → README.COM (1.40)
* [https://archive.org/details/voyeur_202010 Voyeur] → /DEMOS.COM, /README.COM (unknown version)