Xref: utzoo comp.sys.ibm.pc:23719 comp.lang.c:15774
Path: utzoo!utgpu!attcan!uunet!lll-winken!ames!oliveb!amdahl!drivax!alexande
From: alexande@drivax.DRI (Mark Alexander)
Newsgroups: comp.sys.ibm.pc,comp.lang.c
Subject: Re: system() always returns 0?
Summary: possible solution
Keywords: MSC5.0
Message-ID: <4180@drivax.DRI>
Date: 24 Jan 89 17:56:20 GMT
References: <782@hawkmoon.MN.ORG>
Reply-To: alexande@drivax.UUCP (Mark Alexander)
Organization: Bob-ist Temple of Monterey
Lines: 17


One possible solution to the problem of COMMAND.COM always returning
zero is that used by NDMAKE.  The basic idea is to construct on the
fly a little batch file that gets passed to COMMAND.COM.  Before you
call system(), though, you create a little zero-length temporary file.
The batch file runs the subprogram, then checks the errorlevel.  If
the errorlevel is 0, it deletes the temporary file.  Then the main
program gets control again and checks the existence of the temporary
file: if it still exists, an error occurred.

The batch file would look something like this:
	prog [parms...] [<infile] [>outfile]
	if errorlevel 1 goto done
	del tempfile
	:done
-- 
Mark Alexander	(amdahl!drivax!alexande)