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Name

Class::Usul::IPC - List/Create/Delete processes

Synopsis

   use Class::Usul::IPC;

   my $ipc = Class::Usul::IPC->new;

   $result_object = $ipc->run_cmd( [ qw( ls -l ) ] );

Description

Displays the process table and allows signals to be sent to selected processes

Configuration and Environment

Defines these attributes;

cache_ttys

Boolean that defaults to true. Passed to Proc::ProcessTable

Subroutines/Methods

child_list

   @pids = $self->child_list( $pid );

Called with a process id for an argument this method returns a list of child process ids

popen

   $response = $self->popen( $cmd, @opts );

Uses IPC::Open3 to fork a command and pipe the lines of input into it. Returns a Class::Usul::Response::IPC object. The response object's out method returns the STDOUT from the command. Throws in the event of an error. See "run_cmd" for a full list of options and response attributes

process_exists

   $bool = $self->process_exists( file => $path, pid => $pid );

Tests for the existence of the specified process. Either specify a path to a file containing the process id or specify the id directly

process_table

Generates the process table data used by the HTML::FormWidget table subclass. Called by "proc_table" in Class::Usul::Model::Process

run_cmd

   $response = $self->run_cmd( $cmd, $opts );

Runs the given command. If $cmd is a string then an implementation based on the system function is used. If $cmd is an arrayref then an implementation based on IPC::Run is used if it is installed. If IPC::Run is not installed then the arrayref is joined with spaces and the system implementation is used. The keys of the $opts hashref are:

async

If async is true then the command is run in the background

debug

Debug status. Defaults to $self->debug

err

Passing err => q(out) mixes the normal and error output together

in

Input to the command. Can be a string or an array ref

out

Destination for standard output

tempdir

Directory used to store the lock file and lock table if the fcntl backend is used. Defaults to $self->tempdir

Returns a Class::Usul::Response::IPC object or throws an error. The response object has the following methods:

core

Returns true if the command generated a core dump

err

Contains a cleaned up version of the commands STDERR

out

Contains a cleaned up version of the commands STDOUT

pid

The id of the background process. Only set if command is running async

rv

The return value of the command

sig

If the command died as the result of receiving a signal return the signal number

stderr

Contains the commands STDERR

stdout

Contains the commands STDOUT

On MSWin32 the "popen" method is used instead. That method does not support the async option

signal_process

Send a signal the the selected processes. Invokes the suid root wrapper

signal_process_as_root

   $self->signal_process( [{] param => value, ... [}] );

This is called by processes running as root to send signals to selected processes. The passed parameters can be either a list of key value pairs or a hash ref. Either a single pid, or an array ref pids, or file must be passwd. The file parameter should be a path to a file containing process ids one per line. The sig defaults to TERM. If the flag parameter is set to one then the given signal will be sent once to each selected process. Otherwise each process and all of it's children will be sent the signal. If the force parameter is set to true the after a grace period each process and it's children are sent signal KILL

__cleaner

This interrupt handler traps the pipe signal

__handler

This interrupt handler traps the child signal

Diagnostics

None

Dependencies

Class::Usul
Class::Usul::Constants
Class::Usul::Response::IPC
Class::Usul::Response::Table
IPC::Open3
IPC::SysV
Module::Load::Conditional
POSIX
Proc::ProcessTable
Try::Tiny

Incompatibilities

There are no known incompatibilities in this module

Bugs and Limitations

There are no known bugs in this module. Please report problems to the address below. Patches are welcome

Author

Peter Flanigan, <Support at RoxSoft.co.uk>

License and Copyright

Copyright (c) 2014 Peter Flanigan. All rights reserved

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See perlartistic

This program is distributed in the hope that it will be useful, but WITHOUT WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE