Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!uunet!auspex!guy
From: guy@auspex.auspex.com (Guy Harris)
Newsgroups: comp.unix.questions
Subject: Re: redirecting standard i/o from an exec'ed programme
Keywords: popen, io, exec, system
Message-ID: <3939@auspex.auspex.com>
Date: 22 Aug 90 18:22:23 GMT
References: <377@fe2o3.UUCP> <2007@lzga.ATT.COM>
Organization: Auspex Systems, Santa Clara
Lines: 5

>Popen is expensive.  It requires a shell for 'system' and then
>another shell to run your request in.

It doesn't use "system()" on any UNIX implementation I've used (V7, BSD,
S3, S5, etc.).  It just runs *one* shell, which runs your command.