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From: lbr@holos0.uucp (Len Reed)
Newsgroups: comp.unix.xenix.sco
Subject: Re: System call in C
Message-ID: <1991May13.142434.18200@holos0.uucp>
Date: 13 May 91 14:24:34 GMT
References: <53@swatty.UUCP>
Organization: Holos Software, Inc., Atlanta, GA
Lines: 26

In article <53@swatty.UUCP> krone%swatty@attmail.com (Larry Krone) writes:
>I am writing a program in C that issues a command to the shell via the system
>function.  I do not want anything to print from the executed command.
>
>Appending a > /dev/null on the end of the command does not seem to work...

You must redirect stderr (handle 2), too.	      

system("command args >/dev/null 2>/dev/null")
				      
or

system("command args >/dev/null 2>&1")

(The second version says duplicate handle 2 as a copy of 1, which is
of course already open to /dev/null.)

This won't disconnect the process from the tty, though, so if it opens
"/dev/tty" and writes to it stronger measures are required.


-- 
Len Reed
Holos Software, Inc.
Voice: (404) 496-1358
UUCP: ...!gatech!holos0!lbr