NAME Sys::Cmd - run a system command or spawn a system processes VERSION 0.99.0 (2022-10-05) SYNOPSIS use Sys::Cmd qw/run spawn/; # Get command output, raise exception on failure: $output = run(@cmd); # Feed command some input, get output as lines, # raise exception on failure: @output = run( @cmd, { input => 'feedme' } ); # Spawn and interact with a process somewhere else: $proc = spawn( @cmd, { dir => '/', encoding => 'encoding(iso-8859-3)' }, ); while ( my $line = $proc->stdout->getline ) { $proc->stdin->print("thanks\n"); } my @errors = $proc->stderr->getlines; $proc->close(); # Finished talking to file handles $proc->wait_child(); # Cleanup # read exit information $proc->exit(); # exit status $proc->signal(); # signal $proc->core(); # core dumped? (boolean) DESCRIPTION Sys::Cmd lets you run system commands and capture their output, or spawn and interact with a system process through its "STDIN", "STDOUT", and "STDERR" file handles. The following functions are exported on demand by this module: run( @cmd, [\%opt] ) => $output | @output Execute @cmd and return what the command sent to its "STDOUT", raising an exception in the event of error. In array context returns a list instead of a plain string. The first element of @cmd determines what/how things are run: * If it is a relative file name it is executed directly using Proc::Spawn. * If it is a CODE reference (subroutine) Sys::Cmd forks before running it in the child process. This is not supported on Win32. * Everything else is looked up using File::Which and then executed with Proc::Spawn. The command input and environment can be modified with an optional hashref containing the following key/values: dir The working directory the command will be run in. encoding An string value identifying the encoding of the input/output file-handles. Defaults to 'utf8'. env A hashref containing key/values to be added to the current environment at run-time. If a key has an undefined value then the key is removed from the environment altogether. input A string which is fed to the command via its standard input, which is then closed. runx( @cmd, [\%opt] ) => $outerrput | @outerrput The same as the "run" function but with the command's "STDERR" output appended to the "STDOUT" output. spawn( @cmd, [\%opt] ) => Sys::Cmd Return a Sys::Cmd object (documented below) representing the process running @cmd, with attributes set according to the optional \%opt hashref. The first element of @cmd determines the execution method just like the "run()" function. Sys::Cmd objects can of course be created using the standard "new" constructor if you prefer that to the "spawn" function: $proc = Sys::Cmd->new( cmd => \@cmd, dir => '/', env => { SOME => 'VALUE' }, enc => 'iso-8859-3', input => 'feedme', on_exit => sub { my $proc = shift; print $proc->pid .' exited with '. $proc->exit; }, ); Note that Sys::Cmd objects created this way will not lookup the command using File::Which the way the "run", "runx" and "spawn" functions do. CODE references in $cmd[0] are however still recognized and forked off. Sys::Cmd uses Log::Any "debug" calls for logging purposes. An easy way to see the output is to add "use Log::Any::Adapter 'Stdout'" in your program. CONSTRUCTOR new(%args) => Sys::Cmd Spawns a process based on %args. %args must contain at least a "cmd" value, and optionally "encoding", "env", "dir" and "input" values as defined as attributes below. If an "on_exit" subref argument is provided it will be called by the "wait_child" method, which can either be called manually or will be automatically called when the object is destroyed. ATTRIBUTES All attributes are read-only. cmd An array ref containing the command or CODE reference (UNIX only) and its arguments. dir The working directory the command will be run in. encoding An string value identifying the encoding of the input/output file-handles. Defaults to 'utf8'. env A hashref containing key/values to be added to the current environment at run-time. If a key has an undefined value then the key is removed from the environment altogether. input A string which is fed to the command via its standard input, which is then closed. This is a shortcut for printing to, and closing the command's *stdin* file-handle. An empty string will close the command's standard input without writing to it. On some systems, some commands may close standard input on startup, which will cause a SIGPIPE when trying to write to it for which Sys::Cmd will warn. pid The command's process ID. stdin The command's *STDIN* file handle, based on IO::Handle so you can call print() etc methods on it. Autoflush is automatically enabled on this handle. stdout The command's *STDOUT* file handle, based on IO::Handle so you can call getline() etc methods on it. stderr The command's *STDERR* file handle, based on IO::Handle so you can call getline() etc methods on it. exit The command's exit value, shifted by 8 (see "perldoc -f system"). Set by "wait_child()". signal The signal number (if any) that terminated the command, bitwise-added with 127 (see "perldoc -f system"). Set by "wait_child()". core A boolean indicating the process core was dumped. Set by "wait_child()". METHODS cmdline => @list | $str In array context returns a list of the command and its arguments. In scalar context returns a string of the command and its arguments joined together by spaces. close() Close all filehandles to the child process. Note that file handles will automaticaly be closed when the Sys::Cmd object is destroyed. Annoyingly, this means that in the following example $fh will be closed when you tried to use it: my $fh = Sys::Cmd->new( %args )->stdout; So you have to keep track of the Sys::Cmd object manually. wait_child() -> $exit_value Wait for the child to exit using waitpid , collect the exit status and return it. This method sets the *exit*, *signal* and *core* attributes and will also be called automatically when the Sys::Cmd object is destroyed. SEE ALSO Sys::Cmd::Template ALTERNATIVES AnyEvent::Run, AnyEvent::Util, Argv, Capture::Tiny, Child, Forks::Super, IO::Pipe, IPC::Capture, IPC::Cmd, IPC::Command::Multiplex, IPC::Exe, IPC::Open3, IPC::Open3::Simple, IPC::Run, IPC::Run3, IPC::RunSession::Simple, IPC::ShellCmd, IPC::System::Simple, POE::Pipe::TwoWay, Proc::Background, Proc::Fork, Proc::Spawn, Spawn::Safe, System::Command SUPPORT This distribution is managed via github: https://github.com/mlawren/sys-cmd/tree/devel This distribution follows the semantic versioning model: http://semver.org/ Code is tidied up on Git commit using githook-perltidy: http://github.com/mlawren/githook-perltidy AUTHOR Mark Lawrence , based heavily on Git::Repository::Command by Philippe Bruhat (BooK). COPYRIGHT AND LICENSE Copyright 2011-2021 Mark Lawrence This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version.