Ubuntu Manpage: Net::Server::Daemonize - Safe fork and daemonization utilities

Provided by: libnet-server-perl_2.014-1_all

NAME

       Net::Server::Daemonize - Safe fork and daemonization utilities

SYNOPSIS

           use Net::Server::Daemonize qw(daemonize);

           daemonize(
             'nobody',                 # User
             'nobody',                 # Group
             '/var/state/mydaemon.pid' # Path to PID file - optional
           );

DESCRIPTION

       This module is intended to let you simply and safely daemonize your server on systems supporting the
       POSIX module. This means that your Perl script runs in the background, and it's process ID is stored in a
       file so you can easily stop it later.

EXPORTED FUNCTIONS

daemonize
Main routine. Arguments are user (or userid), group (or group id or space delimited list of groups),
and pid_file (path to file). This routine will check on the pid file, safely fork, create the pid
file (storing the pid in the file), become another user and group, close STDIN, STDOUT and STDERR,
separate from the process group (become session leader), and install $SIG{INT} to remove the pid
file. In otherwords - daemonize. All errors result in a die. As of version 0.89 the pid_file is
optional.

safe_fork
Block SIGINT during fork. No arguments. Returns pid of forked child. All errors result in a die.

set_user
Become another user and group. Arguments are user (or userid) and group (or group id or space
delimited list of groups).

set_uid
Become another user. Argument is user (or userid). All errors die.

set_gid
Become another group. Arguments are groups (or group ids or space delimited list of groups or group
ids). All errors die.

get_uid
Find the uid. Argument is user (userid returns userid). Returns userid. All errors die.

get_gid
Find the gids. Arguments are groups or space delimited list of groups. All errors die.

is_root_user
Determine if the process is running as root. Returns 1 or undef.

check_pid_file
Arguments are pid_file (full path to pid_file). Checks for existence of pid_file. If file exists,
open it and determine if the process that created it is still running. This is done first by
checking for a /proc file system and second using a "ps" command (BSD syntax). (If neither of these
options exist it assumed that the process has ended) If the process is still running, it aborts.
Otherwise, returns true. All errors die.

create_pid_file.
Arguments are pid_file (full path to pid_file). Calls check_pid_file. If it is successful (no
pid_file exists), creates a pid file and stores $$ in the file.

unlink_pid_file
Does just that.

AUTHORS

       Jeremy Howard <j+daemonize@howard.fm>

       Program flow, concepts and initial work.

       Paul Seamons <paul@seamons.com>

       Code rework and componentization.  Ongoing maintainer.

LICENSE