p40001@mcomp.UUCP (09/23/86)
== Repeatedly during the past few months I have come across C source specifically for MS-DOS systems, which used names such as "/dev/con" for the console device, most recently in the latest issue of DDJ (Oct 1986), in Alan Holub's listing of a "more" program for MS-DOS. I am aware that under UNIX, devices appear as files in the directory /dev, but was unaware of a similar construct under MS-DOS. Is this notation an undocumented feature of DOS, or a feature of a particular C compiler, or is it simply an error? An unrelated question: Can anyone point me to a source of data cassettes for the Everex Stream-20 tape drive? These are not your usual data cartridges, but look like normal Compact Cassettes, with a 1/4 inch notch slightly off-center in the rear edge. They hold about 20MB of data, and I know they are available from PC Network for about $30; however, I would like both a cheaper and if possible faster source than PC Network. ----------------------------------------------------- Wolf N. Paul, 290 Dogwood, Plano, Tx. 75075 UUCP: ihnp4!convex!mcomp!doulos!wnp or ihnp4!convex!mcomp!p40001 Phone: (214) 578-8023 W.U.ESL: 6283-2882
dan@prairie.UUCP (Daniel M. Frank) (09/28/86)
In article <10800015@mcomp> p40001@mcomp.UUCP writes: >Repeatedly during the past few months I have come across C source >specifically for MS-DOS systems, which used names such as >"/dev/con" for the console device ... >Is this notation an undocumented feature of DOS, or a feature of >a particular C compiler, or is it simply an error? It's an undocumented feature of DOS. You can use the /dev/ pathname notation anywhere you would normally use the device name. -- -------- Dan Frank uucp: ... uwvax!prairie!dan arpa: dan%caseus@spool.wisc.edu
plocher@puff.wisc.edu (John Plocher) (09/28/86)
[fodder]
In reply to the notation behind /dev/con as used under MS-DOS:
DOS parses the filename into three parts:
PATH \ FILENAME . TYPE
If FILENAME is a known device (CON, COM1, PRN, NUL...) then
the file request goes directly to that device driver.
Thus MASM... use the filename NUL.LST etc to denote
the bit bucket.
In this light, the /dev is completely ignored, in fact
you *could* use /foo/bar/foobar/nul.tmp as another name for the
bit-bucket.
There is an undoccumented DOS call (at least in 2.1) which
makes device names completely significant (path\filename.type)
but I don't know of ANYONE who uses it.
--
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