/usr/share/perl5/Proc/Background/Unix.pm is in libproc-background-perl 1.10-1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 | # Proc::Background::Unix: Unix interface to background process management.
#
# Copyright (C) 1998-2005 Blair Zajac. All rights reserved.
package Proc::Background::Unix;
require 5.004_04;
use strict;
use Exporter;
use Carp;
use POSIX qw(:errno_h :sys_wait_h);
use vars qw(@ISA $VERSION);
@ISA = qw(Exporter);
$VERSION = sprintf '%d.%02d', '$Revision: 1.10 $' =~ /(\d+)\.(\d+)/;
# Start the background process. If it is started sucessfully, then record
# the process id in $self->{_os_obj}.
sub _new {
my $class = shift;
unless (@_ > 0) {
confess "Proc::Background::Unix::_new called with insufficient number of arguments";
}
return unless defined $_[0];
# If there is only one element in the @_ array, then it may be a
# command to be passed to the shell and should not be checked, in
# case the command sets environmental variables in the beginning,
# i.e. 'VAR=arg ls -l'. If there is more than one element in the
# array, then check that the first element is a valid executable
# that can be found through the PATH and find the absolute path to
# the executable. If the executable is found, then replace the
# first element it with the absolute path.
my @args = @_;
if (@_ > 1) {
$args[0] = Proc::Background::_resolve_path($args[0]) or return;
}
my $self = bless {}, $class;
# Fork a child process.
my $pid;
{
if ($pid = fork()) {
# parent
$self->{_os_obj} = $pid;
$self->{_pid} = $pid;
last;
} elsif (defined $pid) {
# child
exec @_ or croak "$0: exec failed: $!\n";
} elsif ($! == EAGAIN) {
sleep 5;
redo;
} else {
return;
}
}
$self;
}
# Wait for the child.
sub _waitpid {
my $self = shift;
my $timeout = shift;
{
# Try to wait on the process.
my $result = waitpid($self->{_os_obj}, $timeout ? 0 : WNOHANG);
# Process finished. Grab the exit value.
if ($result == $self->{_os_obj}) {
return (0, $?);
}
# Process already reaped. We don't know the exist status.
elsif ($result == -1 and $! == ECHILD) {
return (1, 0);
}
# Process still running.
elsif ($result == 0) {
return (2, 0);
}
# If we reach here, then waitpid caught a signal, so let's retry it.
redo;
}
return 0;
}
sub _die {
my $self = shift;
# Try to kill the process with different signals. Calling alive() will
# collect the exit status of the program.
SIGNAL: {
foreach my $signal (qw(HUP QUIT INT KILL)) {
my $count = 5;
while ($count and $self->alive) {
--$count;
kill($signal, $self->{_os_obj});
last SIGNAL unless $self->alive;
sleep 1;
}
}
}
}
1;
__END__
=head1 NAME
Proc::Background::Unix - Unix interface to process mangement
=head1 SYNOPSIS
Do not use this module directly.
=head1 DESCRIPTION
This is a process management class designed specifically for Unix
operating systems. It is not meant used except through the
I<Proc::Background> class. See L<Proc::Background> for more information.
=head1 AUTHOR
Blair Zajac <blair@orcaware.com>
=head1 COPYRIGHT
Copyright (C) 1998-2005 Blair Zajac. All rights reserved. This
package is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
=cut
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