Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!haven!adm!cmcl2!phri!marob!rogol
From: rogol@marob.MASA.COM (Fred Buck)
Newsgroups: comp.unix.questions
Subject: Re: sh script hangs after first external command
Message-ID: <578@marob.MASA.COM>
Date: 6 Mar 89 17:06:07 GMT
References: <3642@datapg.MN.ORG>
Reply-To: rogol@marob.masa.com (Fred Buck)
Distribution: na
Organization: Today Organization, Tomorrow Chaos
Lines: 19

In article <3642@datapg.MN.ORG> sewilco@DataPg.MN.ORG (Scot E Wilcoxon) writes:
>A program is doing a system(3) call to execute a shell script.
>The script hangs after doing the first command which is not a shell
>builtin.  Any ideas what can do that?
>
>This problem is taking place in a System V.2 Honeywell-Bull XPS-100

A shell that doesn't get the expected results from SIGCLD will hang
after the first external command, since it can't tell when the child
exits.  Typically this is caused by ignoring SIGCLD before forking the
child.  Try a signal(SIGCLD,SIG_DFL) before your system() call.  If this
fixes the problem, then make provisions to save the previous vector
for SIGCLD and to restore it after system() returns.

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