http://qs321.pair.com?node_id=865615

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

I want to use them, because according to the document, SIGRTs can be queued while multiple signals come. However, the program just exit: 
#!/usr/bin/perl

use common::sense;
use Glib qw/TRUE FALSE/;

$SIG{'SIGRTMIN+5'} = \&on_sig;

my $loop = Glib::MainLoop->new( 'default', FALSE );
$loop->run;

sub on_sig {
    my $sig = shift;
    say "somebody told me $sig";
}

[download]
send him a min+5 
$ ./t_signal.pl &
[2] 3305
$ kill -s SIGRTMIN+5 3305
$ 
[2]+  Real-time signal 5      ./t_signal.pl
$

[download]
Why?

Replies are listed 'Best First'.
Re: Unix real time signals
by zwon (Abbot) on Oct 16, 2010 at 09:32 UTC

    The following code should do the trick: 

    use strict;
use warnings;

use Config;
use List::MoreUtils qw(firstidx);

my @signals = split / /, $Config{sig_name};
my $rtmin = firstidx { $_ eq 'RTMIN' } @signals;
my $rt5name = $signals[ $rtmin + 5 ];
print "They call it $rt5name\n";

$SIG{$rt5name} = sub { warn "caught it!\n" };

sleep 10 while 42;

    [download]
[reply]
[d/l]
Re: Unix real time signals
by lidden (Curate) on Oct 16, 2010 at 03:15 UTC
    Try without the SIG part. I.e: $SIG{'RTMIN+5'} = \&on_sig;
[reply]
[d/l]
      If you "use warnings" you'll see:

      No such signal: SIGSIGRTMIN+5 at rt.pl line 5.

      I can't get anything to work with the +5 stuff, but this code works: 

      #!/usr/bin/perl
use strict;
use warnings;

$SIG{'RTMIN'} = \&on_sig;

print $$, "\n";
while (1) {
    sleep 1;
    print ".\n";
}

sub on_sig {
    my $sig = shift;
    print "somebody told me $sig";
}

      [download]

      When I send it a signal like this:

      $ kill -s SIGRTMIN 763

      I get:

      somebody told me RTMIN.

      -sam

      (Wow, I've been gone too long. This was supposed to be a reply to the original question!)

[reply]
[d/l]
[select]
        I thought first 3 RT signals are conserved by something. I forgot where I seen that...
[reply]

Back to Seekers of Perl Wisdom