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Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!att!cbnewsl!mpl
From: mpl@cbnewsl.ATT.COM (michael.p.lindner)
Newsgroups: comp.lang.c,comp.unix.wizards
Subject: Re: redirect stdin when using execl
Summary: use system(3)
Keywords: execl redirect stdin <
Message-ID: <769@cbnewsl.ATT.COM>
Date: 9 Jun 89 20:07:47 GMT
References: <414@sc50.UUCP>
Organization: AT&T Bell Laboratories
Lines: 24

In article <414@sc50.UUCP>, ron@sc50.UUCP ( Ron Winnacott ) writes:
> Hello net.
> execl("/bin/mail","mail","ron","<","/tmp/tfile",NULL);
> Ron Winacott.  Unisys Canada, Support center.

The problem is that the "<" meaning redirection is a feature of the shell,
not the operating system execl() call.  You can call system, described in
section 3 of your programmer's guide, instead, such as:

	char	buffer[32];	/* make sure it's big enough */
	char	*ron = "ron";	/* or whoever */
	char	*tempfile = "/tmp/tfile"; /* or whatever */

	sprintf(buffer, "/bin/mail %s < %s", ron, tempfile);
	if (system(buffer) == 0)
		/* yay! I sent mail! */ ;
	else
		/* boo!  It failed! */ ;

Mike Lindner
attunix!mpl
AT&T
190 River Rd.
Summit, NJ 17901