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From: "Rod Pemberton" <dont_use_email AT xnothavet DOT cqm>
Newsgroups: comp.os.msdos.djgpp,comp.os.msdos.programmer
Subject: Why does PROMPT accept 128 characters if the command line is only
 126?
Date: Thu, 10 Apr 2014 20:39:43 -0400
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If the command line is 126 characters, why does PROMPT accept 128?

In MS-DOS v7.10 (in real mode and Windows SE console), PROMPT will
accept upto 128 characters for a new prompt, when using a single
character prompt.  E.g.,

   PROMPT $Q
   PROMPT <...enter 128 characters...>

RBIL says 128 bytes are available in the PSP, two of which are in-use.
DJGPP says MAX_INPUT is 126 in limits.h.

I'm hoping someone knows why this is off by two ...


Rod Pemberton