[32763] in Perl-Users-Digest
Perl-Users Digest, Issue: 4027 Volume: 11
daemon@ATHENA.MIT.EDU (Perl-Users Digest)
Fri Sep 6 11:09:43 2013
Date: Fri, 6 Sep 2013 08:09:02 -0700 (PDT)
From: Perl-Users Digest <Perl-Users-Request@ruby.OCE.ORST.EDU>
To: Perl-Users@ruby.OCE.ORST.EDU (Perl-Users Digest)
Perl-Users Digest Fri, 6 Sep 2013 Volume: 11 Number: 4027
Today's topics:
thread problem <dave@invalid.invalid>
Digest Administrivia (Last modified: 6 Apr 01) (Perl-Users-Digest Admin)
----------------------------------------------------------------------
Date: Fri, 6 Sep 2013 13:27:46 +0000 (UTC)
From: "Dave Saville" <dave@invalid.invalid>
Subject: thread problem
Message-Id: <fV45K0OBJxbE-pn2-FIfVXiZqy6dP@paddington.bear.den>
I am having a problem with threads on a Raspberry Pi. (Note - have
never used threads in perl. Only C)
use strict;
use warnings;
use threads;
use threads::shared;
my $foo = 'foo';
threads->create({'void' => 1}, 'try');
sleep 2;
print "$foo - done\n";
sleep 5;
sub try
{
threads->detach();
$foo = 'bar';
sleep 5;
return;
}
Why isn't $foo changing in the main thread? I have tried passing $foo
as an argument to try both as itself and as a scalar ref. No way can I
get $foo to change value in main.
What I am trying to do is use a thread to essentially tail a pipe and
raise a flag in main if it sees a certain string appear.The main
thread can't tail it because I don't want to block. So my "real* sub
is:
sub get_title
{
threads->detach();
my $ref = shift;
open my $FIFO, '<', '/home/pi/fifo_stdout' or die "Can't open
fifo_stdout $!";
while ( <$FIFO> )
{
if ( m{^StreamTitle='([^']*)'} )
{
$$ref = $1;
}
}
}
--
Regards
Dave Saville
------------------------------
Date: 6 Apr 2001 21:33:47 GMT (Last modified)
From: Perl-Users-Request@ruby.oce.orst.edu (Perl-Users-Digest Admin)
Subject: Digest Administrivia (Last modified: 6 Apr 01)
Message-Id: <null>
Administrivia:
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End of Perl-Users Digest V11 Issue 4027
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