Re^2: How do you launch a background process and get pid?

Thanks. I found this thread for suppressing the output:http://www.perlmonks.org/?node_id=53870 The code now looks like this:

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

my $pid = fork;
if ((defined $pid) && ($pid == 0))
{
   open(STDOUT, "/dev/null");          # suppressing output  
   open(STDERR, "/dev/null");          # suppressing output

   exec("sleep", "30");
   exit;
}

print "child pid [$pid]\n";
[download]

Comment on Re^2: How do you launch a background process and get pid? Download Code

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Re^3: How do you launch a background process and get pid? by afoken (Chancellor) on Apr 18, 2016 at 17:12 UTC
`open(STDOUT, "/dev/null"); # suppressing output open(STDERR, "/dev/null"); # suppressing output` [download] Yes, this suppresses output, but accidentally. You open STDOUT and STDERR for input. That may confuse your child process. What you really want is the three-argument form of open, used for output: `open STDOUT,'>','/dev/null'; open STDERR,'>','/dev/null';` [download] Alexander -- Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)	[reply] [d/l] [select]

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Re^3: How do you launch a background process and get pid?
by afoken (Chancellor) on Apr 18, 2016 at 17:12 UTC

open(STDOUT, "/dev/null");          # suppressing output  
open(STDERR, "/dev/null");          # suppressing output
[download]

Yes, this suppresses output, but accidentally. You open STDOUT and STDERR for input. That may confuse your child process. What you really want is the three-argument form of open, used for output:

open STDOUT,'>','/dev/null';
open STDERR,'>','/dev/null';
[download]

Alexander

--
Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

[reply]
[d/l]
[select]