vi-like editor for the IBM PC

Billy G. Allie bga at bgalli.eds.com
Sat Mar 4 15:13:13 AEST 1989


In article <7374 at killer.DALLAS.TX.US>, wnp at killer.DALLAS.TX.US (Wolf Paul) writes:
< [refering to the MKS cpio command]
< Very good! It has a (non-standard) option to compress each file before
< adding it to the archive; unfortunately limited by the fact that MKS'
< compress does not support 16-bit compression. Another limitation is 
< that of course, such compressed cpio archives are not directly
< unpackable under UNIX -- you have to unpack them, and then manually
< run each extracted file through uncompress.

Archives created with the -z (non-standard) option of the MKS cpio command
can be unpacked with the following command (filename is the name of the
compressed archive file):

	zcat filename | cpio -ic

assuming that the '-c' option was used in creating the archive.  In fact the
'-z' option is meant equivalent with the following pipelines:

	MKS command		     UNIX pipeline
	----------------------       ---------------------------------------
	cpio -oz<other options> <--> cpio -o<other options> | compress -b 14
	cpio -iz<other options> <--> uncompress | cpio -i<other options>

BTW, the -z option was added because MS-DOS does not have multi-tasking or
true pipes.  To compress the archive on MS-DOS using pipes would require
a temporary file big enough to hold the content of the entire archive.  By
building the compression into cpio, this temporary file is not needed.

< [refering to the MKS compress, uncompress and zcat commands]
< Unfortunately these handle only 12-bit compression and can't handle
< UNIX-compressed files (usually 16-bit)

These commands can handle up to 14-bit compression modes.  This is not a
great concern to me since I have a version of compress that will handle
16-bit compression on MS-DOS.

One fact that wasn't mentioned is the capability of the MKS Korn shell has
of passing up to 5Kbytes of arguments to the MS-DOS programs.  Of course, the
programs must know how to access these arguments (all MKS toolkit programs do
this).

I have no connection to MKS except as a satisfied customer.
-- 
____	   | Billy G. Allie	| Internet..: bga at bgalli.eds.com
|  /|	   | 7436 Hartwell	| UUCP......: uunet!{mcf|edsews}!bgalli!bga
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|/  |LLIE  | (313) 582-1540	| Genie.....: BGALLIE



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