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net::server::sig(3) [osx man page]

Net::Server::SIG(3)					User Contributed Perl Documentation				       Net::Server::SIG(3)

Net::Server::SIG - adpf - Safer signal handling SYNOPSIS
use Net::Server::SIG qw(register_sig check_sigs); use IO::Select (); use POSIX qw(WNOHANG); my $select = IO::Select->new(); register_sig(PIPE => 'IGNORE', HUP => 'DEFAULT', USR1 => sub { print "I got a SIG $_[0] "; }, USR2 => sub { print "I got a SIG $_[0] "; }, CHLD => sub { 1 while waitpid(-1, WNOHANG) > 0; }, ); # add some handles to the select $select->add(*STDIN); # loop forever trying to stay alive while(1) { # do a timeout to see if any signals got passed us # while we were processing another signal my @fh = $select->can_read(10); my $key; my $val; # this is the handler for safe (fine under unsafe also) if (check_sigs()) { # or my @sigs = check_sigs(); next unless @fh; } my $handle = $fh[@fh]; # do something with the handle } DESCRIPTION
Signals prior in Perl prior to 5.7 were unsafe. Since then signals have been implemented in a more safe algorithm. Net::Server::SIG provides backwards compatibility, while still working reliably with newer releases. Using a property of the select() function, Net::Server::SIG attempts to fix the unsafe problem. If a process is blocking on select() any signal will short circuit the select. Using this concept, Net::Server::SIG does the least work possible (changing one bit from 0 to 1). And depends upon the actual processing of the signals to take place immediately after the the select call via the "check_sigs" function. See the example shown above and also see the script located in the examples directory of this distribution. FUNCTIONS
"register_sig($SIG => &code_ref)" Takes key/value pairs where the key is the signal name, and the argument is either a code ref, or the words 'DEFAULT' or 'IGNORE'. The function register_sig must be used in conjuction with check_sigs, and with a blocking select() function call -- otherwise, you will observe the registered signal mysteriously vanish. "unregister_sig($SIG)" Takes the name of a signal as an argument. Calls register_sig with a this signal name and 'DEFAULT' as arguments (same as register_sig(SIG,'DEFAULT') "check_sigs()" Checks to see if any registered signals have occured. If so, it will play the registered code ref for that signal. Return value is array containing any SIGNAL names that had occured. "sig_is_registered($SIG)" Takes a signal name and returns any registered code_ref for that signal. AUTHORS
Paul Seamons ( Rob B Brown ( - Provided a sounding board and feedback in creating Net::Server::SIG and LICENSE
This package may be distributed under the terms of either the GNU General Public License or the Perl Artistic License All rights reserved. perl v5.16.2 2012-05-29 Net::Server::SIG(3)

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Net::Server::Fork(3)					User Contributed Perl Documentation				      Net::Server::Fork(3)

Net::Server::Fork - Net::Server personality SYNOPSIS
use base qw(Net::Server::Fork); sub process_request { #...code... } __PACKAGE__->run(); DESCRIPTION
Please read the pod on Net::Server first. This module is a personality, or extension, or sub class, of the Net::Server module. This personality binds to one or more ports and then waits for a client connection. When a connection is received, the server forks a child. The child handles the request and then closes. With the exception of parent/child signaling, this module will work (with basic functionality) on Win32 systems. ARGUMENTS
check_for_dead Number of seconds to wait before looking for dead children. This only takes place if the maximum number of child processes (max_servers) has been reached. Default is 60 seconds. max_servers The maximum number of children to fork. The server will not accept connections until there are free children. Default is 256 children. max_dequeue The maximum number of dequeue processes to start. If a value of zero or undef is given, no dequeue processes will be started. The number of running dequeue processes will be checked by the check_for_dead variable. check_for_dequeue Seconds to wait before forking off a dequeue process. It is intended to use the dequeue process to take care of items such as mail queues. If a value of undef is given, no dequeue processes will be started. CONFIGURATION FILE
See Net::Server. PROCESS FLOW
Process flow follows Net::Server until the post_accept phase. At this point a child is forked. The parent is immediately able to wait for another request. The child handles the request and then exits. HOOKS
The Fork server has the following hooks in addition to the hooks provided by the Net::Server base class. See Net::Server "$self->child_init_hook()" This hook is called just after the fork and after signals have been cleaned up. "$self->pre_accept_hook()" This hook occurs just before the accept is called. "$self->pre_fork_hook()" This hook occurs just after accept but before the fork. "$self->post_accept_hook()" This hook occurs in the child after the accept and fork. "$self->run_dequeue()" This hook only gets called in conjuction with the check_for_dequeue setting. HOT DEPLOY
Since version 2.000, the Fork server has accepted the TTIN and TTOU signals. When a TTIN is received, the max_servers is increased by 1. If a TTOU signal is received the max_servers is decreased by 1. This allows for adjusting the number of handling processes without having to restart the server. AUTHOR
Paul Seamons <> Rob Brown <> SEE ALSO
Please see also Net::Server::INET, Net::Server::PreFork, Net::Server::MultiType, Net::Server::SIG Net::Server::Single perl v5.16.2 2012-06-19 Net::Server::Fork(3)
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