No effect with SIG{INT}

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Dear Monks,

I've tried the following:

#! /usr/bin/perl

use Config;

select STDOUT ; $| = 1 ;
while ( true ) {
    print "." ;
    sleep 1 ;
}

sub catch_zap {
    die "Somebody sent me a SIG$signame";
}
#$SIG{INT} = 'catch_zap';  # could fail in modules
$SIG{INT} = \&catch_zap;  # best strategy
[download]

Without success.
Any suggestion what I'm doing wrong ?

Thanks in advance
Luca

Comment on No effect with SIG{INT} Download Code

Replies are listed 'Best First'.
Re: No effect with SIG{INT} by borisz (Canon) on Jan 16, 2006 at 10:24 UTC
thats easy, just install the sighandler before you start your mainloop ;-) `sub catch_zap { die "Somebody sent me a SIG$signame"; } $SIG{INT} = 'catch_zap'; # could fail in modules select STDOUT ; $\| = 1 ; while ( true ) { print "." ; sleep 1 ; }` [download] Boris	[reply] [d/l]
Re: No effect with SIG{INT} by Anonymous Monk on Jan 16, 2006 at 12:19 UTC
Now I have the problem that `SIG{INT} = \&close()` is executed at the beginning of the program. I'm using an object now, so when Ctrl-C is pressed this object has to be closed properly, like: `#main $obj = DBConnect->new ; $SIG{INT} = \&close ; .... .... sub close { $obj->close ; exit ; }` [download] Any suggestions why this is wrong ? Luca	[reply] [d/l] [select]
Re^2: No effect with SIG{INT} by borisz (Canon) on Jan 16, 2006 at 13:38 UTC
your example work. And close is NOT called. I guess you wrote `$SIG{INT} = \&close();` that line call close. You want `$SIG{INT} = \&close`. `$SIG{INT} = \&close(); # wrong $SIG{INT} = \&close; # ok` [download] Boris	[reply] [d/l]
Re^2: No effect with SIG{INT} by ysth (Canon) on Jan 17, 2006 at 01:18 UTC
To amplify on what borisz said, `\&close()` is a reference to the value returned by close(), while `\&close` is a reference to sub close (which need not have already been defined).	[reply] [d/l] [select]