hdf5/bin/runbkgprog
Larry Knox 11dfa25910
Update copyright headers (#2184)
* Updated source file copyright headers to remove "Copyright by the Board of Trustees
of the University of Illinois", which is kept in the top-level COPYING file.
2022-11-01 16:02:27 -05:00

88 lines
2.4 KiB
Perl
Executable File

#!/usr/bin/env perl
require 5.003;
use warnings;
$indent=4;
#
# Copyright by The HDF Group.
# All rights reserved.
#
# This file is part of HDF5. The full HDF5 copyright notice, including
# terms governing use, modification, and redistribution, is contained in
# the COPYING file, which can be found at the root of the source code
# distribution tree, or in https://www.hdfgroup.org/licenses.
# If you do not have access to either file, you may request a copy from
# help@hdfgroup.org.
#
# Run program in background
#
use warnings;
use strict;
use Carp;
use Time::HiRes;
use POSIX 'setsid';
my $child_pid;
my $child_proc;
my $cmd = $ARGV[0];
my $debug = 1;
print "\nStart child process\n";
start_child();
print "\nStarted child process\n";
sub start_child {
die "cannot execute cmd: $cmd" unless -x $cmd;
if ($^O eq 'MSWin32') { # Windows
require Win32::Process;
Win32::Process::Create($child_proc, $cmd, $cmd, 0, 0, ".") || confess "Could not spawn child: $!";
$child_pid = $child_proc->GetProcessID();
}
else { # Unix
$SIG{CHLD} = 'IGNORE';
$child_pid = fork();
unless (defined $child_pid) {
confess "Could not spawn child (Unix): $!";
}
if ($child_pid == 0) { # child
unless ($debug) {
open STDIN, "<", "/dev/null" or die "Can't read /dev/null: $!";
open STDOUT, ">", "/dev/null" or die "Can't write /dev/null: $!";
}
setsid or warn "setsid cannot start a new session: $!";
unless ($debug) {
open STDERR, '>&STDOUT' or die "Can't dup stdout: $!";
}
local $| = 1;
unless (exec($cmd)) {
confess "Could not start child: $cmd: $!";
CORE::exit(0);
}
}
# parent
$SIG{CHLD} = 'DEFAULT';
}
# catch early child exit, e.g. if program path is incorrect
sleep(1.0);
POSIX::waitpid(-1, POSIX::WNOHANG()); # clean up any defunct child process
if (kill(0,$child_pid)) {
print "\nStarted child process id $child_pid\n";
}
else {
warn "Child process exited quickly: $cmd: process $child_pid";
}
}
sub stop_child
{
if ($^O eq 'MSWin32') { # Windows
Win32::Process::KillProcess($child_pid,0);
}
else { # Unix
kill 9, $child_pid || warn "could not kill process $child_pid: $!";
}
print "Stopped child process id $child_pid\n";
}