moderated, Shielding system() from SIGINT

comp.lang.perl.moderated - Perl language. (Moderated)


moderated >> Shielding system() from SIGINT

by Daniel E. Macks » Wed, 23 Mar 2005 00:32:47 GMT

I've got a perl script that uses system() to spawn a program that
should not be interrupted. I can't modify that subprogram itself, so I
currently do:

{
local $SIG{INT} = 'IGNORE';
system("some_thing");
}

That works (the perl process ignores SIGINT, preventing it from
getting to the some_thing process) but we want to be more friendly,
and let the user know why control-C didn't kill the process. How do I
catch the SIGINT and print a msg, but not propagate the sig to the
spawned process?

I thought I wanted:
local $SIG{INT} = sub { print "not interrupt allowed at this time\n" };
but that still results in my some_thing process aborting.

Interestingly, this appears to contradict perlfaq8 ("How do I make a
system() exit on control-C?"), which says I need two write a handler
in the parent to propagate the SIGINT To the system()'ed process.

I'm on OS X, using 5.8.1 (part of Apple's 10.3.x system) or 5.8.6
(compiled by Fink).

dan

--
Daniel Macks
XXXX@XXXXX.COM
http://www.netspace.org/~dmacks
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moderated >> Shielding system() from SIGINT

by Daniel E. Macks » Sun, 27 Mar 2005 06:46:10 GMT


black nationalist. But
since it's the natural tendency for leaders to be jealous and look upon
a powerful figure like Graham with suspicion and envy, how is it
possible for him to come into a city and get all the cooperation of the
church leaders? Don't think because they're church leaders that they
don't have weaknesses that make them envious and jealous -- no,
everybody's got it. It's not an accident that when they want to choose a
cardinal, as Pope I over there in Rome, they get in a closet so you
can't hear them cussing and fighting and carrying on.

Billy Graham comes in preaching the gospel of Christ. He evangelizes the
gospel. He stirs everybody up, but he never tries to start a church. If
he came in trying to start a church, all the churches would be against
him. So, he just comes in talking about Christ and tells everybody who
gets Christ to go to any church where Christ is; and in this way the
church cooperates with him. So we're going to take a page from his book.

Our gospel is black nationalism. We're not trying to threaten the
existence of any organization, but we're spreading the gospel of black
nationalism. Anywhere there's a church that is also preaching and
practicing the gospel of black nationalism, join that church. If the
NAACP is preaching and practicing the gospel of black nationalism, join
the NAACP. If CORE is spreading and practicing the gospel of black
nationalism, join CORE. Join any organization that has a gospel that's
for the uplift of the black man. And when you get into it and see them
pussyfooting or compromising, pull out of it because that's not black
nationalism. We'll find another one.

And in this manner, the organizations will increase in number and in
quantity and in quality, and by August, it is then our intention to have
a black nationalist convention which will consist o
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Similar Threads

1. SIGINT not blocked by system()? 

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According to perlfaq8, system() is shielded from SIGINT:

-----------------------------------------------------------------------------
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On Friday, Nov 14, 2003, at 18:39 US/Pacific, Jerry Rocteur wrote:

> Beautiful drieux, what a sexy way to do a system call!!
>
> And I never knew about $host = hostname;.. What a neat trick..
>
> Keep 'em comin...

Wiggins is the one who deserves the point,
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---

6. Reading RMS files on a OpenVMS system from a WIN32 system - Perl

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I am calling the same FTP site each time and using the same version of
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Frank Bright
Univ. of the Arts
215.717.6081
 XXXX@XXXXX.COM

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