NAME

       Proc::Background::Unix - Unix-specific implementation of process create/wait/kill

DESCRIPTION

       This module does not have a public interface.  Use Proc::Background.

NAME

       Proc::Background::Unix - Implementation of process management for Unix systems

IMPLEMENTATION

   Command vs. Exec
       Unix systems start a new process by creating a mirror of the current process ("fork") and
       then having it alter its own state to prepare for the new program, and then calling "exec"
       to replace the running code with code loaded from a new file.  However, there is a second
       common method where the user wants to specify a command line string as they would type it
       in their shell.  In this case, the actual program being executed is the shell, and the
       command line is given as one element of its argument list.

       Perl already supports both methods, such that if you pass one string to "exec" containing
       shell characters, it calls the shell, and if you pass multiple arguments, it directly
       invokes "exec".

       This module mostly just lets Perl's "exec" do its job, but also checks for the existence
       of the executable first, to make errors easier to catch.  This check is skipped if there
       is a single-string command line.

       Unix lets you run a different executable than what is listed in the first argument.  (this
       feature lets one Unix executable behave as multiple different programs depending on what
       name it sees in the first argument) You can use that feature by passing separate options
       of "exe" and "command" to this module's constructor instead of a simple argument list.
       But, you can't mix a "exe" option with a shell-interpreted command line string.

   Errors during Exec
       If the "autodie" option is enabled, and the system supports "FD_CLOEXEC", this module uses
       a trick where the forked child relays any errors through a pipe so that the parent can
       throw and handle the exception directly instead of creating a child process that is dead-
       on-arrival with the error on STDERR.

AUTHORS

       •   Blair Zajac <blair@orcaware.com>

       •   Michael Conrad <mike@nrdvana.net>

VERSION

       version 1.30

COPYRIGHT AND LICENSE

       This software is copyright (c) 2021 by Michael Conrad, (C) 1998-2009 by Blair Zajac.

       This is free software; you can redistribute it and/or modify it under the same terms as
       the Perl 5 programming language system itself.