NAME
P9Y::ProcessTable - Portably access the process table
SYNOPSIS
use P9Y::ProcessTable;
my @process_table = P9Y::ProcessTable->table;
print $process_table[0]->pid."\n";
my @pids = P9Y::ProcessTable->list;
my $perl_process = P9Y::ProcessTable->process;
my $other_process = P9Y::ProcessTable->process($pids[0]);
if ($other_process->has_threads) {
print "# of Threads: ".$other_process->threads."\n";
sleep 2;
$other_process->refresh;
print "# of Threads: ".$other_process->threads."\n";
}
# A cheap and sleazy version of ps
my $FORMAT = "%-6s %-10s %-8s %-24s %s\n";
printf($FORMAT, "PID", "TTY", "STAT", "START", "COMMAND");
foreach my $p ( P9Y::ProcessTable->table ) {
printf($FORMAT,
$p->pid,
$p->ttydev,
$p->state,
scalar(localtime($p->start)),
$p->cmdline,
);
}
# Dump all the information in the current process table
foreach my $p ( P9Y::ProcessTable->table ) {
print "--------------------------------\n";
foreach my $f (P9Y::ProcessTable->fields) {
my $has_f = 'has_'.$f;
print $f, ": ", $p->$f(), "\n" if ( $p->$has_f() );
}
}
DESCRIPTION
This interface will portably access the process table, no matter what
the OS, and normalize its outputs to work similar across all platforms.
METHODS
All methods to this module are actually class-based (objectless) calls.
However, the P9Y::ProcessTable::Process returns are actual objects.
fields
Returns a list of the field names supported by the module on the current
architecture.
list
Returns a list of PIDs that are available in the process table. On most
systems, this is a less heavy call than "table", as it doesn't have to
look up the information for every single process.
table
Returns a list of P9Y::ProcessTable::Process objects for all of the
processes in the process table. (More information in that module POD.)
process
Returns a P9Y::ProcessTable::Process object for the process specified.
If a process isn't specified, it will look up $$ (or its platform
equivalent).
P9Y?
Portability. You know, like I18N and L10N.
SUPPORTED PLATFORMS
Currently, this module supports:
* All "/proc" friendly OSs to some degree. Linux, Solaris, and most
"/proc" friendly BSD-variants are fully supported so far.
* Windows (most flavors)
* Darwin (see CAVEATS)
* FreeBSD (only; see CAVEATS)
* OS/2 (hey, the module was there...)
* VMS (same here; probably needs some testing)
HISTORY
This module spawned because Proc::ProcessTable has fallen into bugland
<http://matrix.cpantesters.org/?dist=Proc-ProcessTable-0.45> for the
last 4 years, and many people just want to be able to get a simple
"PID+cmdline" from the process table. While this module offers more than
that as a bonus, the goal of this module is to have something that JFW,
and continues to JFW.
With that in mind, here my list of what went wrong with
Proc::ProcessTable. I have nothing against the authors of that module,
but I feel like we should try to learn from our failures and adapt in
kind.
* Too many OSs in one distribution. I dunno about you, but I don't
happen to have 15 different OSs on VMs anywhere. At best, I might
have access to 2-3 different platforms. So, trying to test out code
on a platform that you don't actually own is especially difficult.
Thus, this module is merely a wrapper around various other modules
that provide process table information. Those guys actually have the
means (and the drive) to test their stuff on those OSs. (The sole
exception is the ProcFS module, but that may get split eventually.)
* Too much C/XS code. The C and XS code falls in a class of
exclusivity that makes it even harder to maintain. If I were to
conjure up some wild guess, I would say that only 20% of Perl
programmers could actually read, understand, and program C/XS code.
People aren't calling the process table a 1000 times a second, so
there's really no need for a speed boost, either.
Alas, sometimes this is unavoidable, with the process information
buried in C library calls. However, the "/proc" FS is available on a
great many amount of UNIX platforms, so it should be used *as much
as possible*. Also, I take this moment to shake my tiny little fist
at the BSD folks for actually regressing the OS by removing support
for "/proc". All of the reasons behind it are unsound or have
solutions that don't involve removing this most basic right of UNIX
users.
CAVEATS / TODO
* No support for any non-proc BSD system other than FreeBSD. This is
because BSD::Process only supports FreeBSD. If the support is
needed, bug that module maintainer and provide some patches. Then
bug me and I'll change the OS detection logic.
* This thing actually uses Proc::ProcessTable for Darwin/OSX systems.
Darwin doesn't have a "/proc" access point (BSD... sigh).
Fortunately, P:PT is passing all Darwin tests (so far), so until
somebody splits the code from that to a new module (hint hint)...
* Certain other "/proc" friendly OSs needs further support. Frankly,
I'm trying to get a feel for what people actually need than just
spending the time coding something for, say, NeXT OS and 50 other
flavors. However, supporting one OS or another should be pretty
easy. If you need support, dive into the "ProcFS" code and submit a
patch.
* One would say that the class-based calling of ProcessTable (vs. the
more traditional OO model of P9Y:PT:Process) is confusing. I tend to
agree, but it was modeled after Proc:PT's calling scheme.
* See P9Y::ProcessTable::Process for other caveats.
SEE ALSO
* Proc::ProcessTable
* BSD::Process
* Win32::Process::Info & Win32::Process
* OS2::Process
* VMS::Process
AVAILABILITY
The project homepage is
<https://github.com/SineSwiper/P9Y-ProcessTable/wiki>.
The latest version of this module is available from the Comprehensive
Perl Archive Network (CPAN). Visit <http://www.perl.com/CPAN/> to find a
CPAN site near you, or see
<https://metacpan.org/module/P9Y::ProcessTable/>.
SUPPORT
Internet Relay Chat
You can get live help by using IRC ( Internet Relay Chat ). If you don't
know what IRC is, please read this excellent guide:
<http://en.wikipedia.org/wiki/Internet_Relay_Chat>. Please be courteous
and patient when talking to us, as we might be busy or sleeping! You can
join those networks/channels and get help:
* irc.perl.org
You can connect to the server at 'irc.perl.org' and talk to this
person for help: SineSwiper.
Bugs / Feature Requests
Please report any bugs or feature requests via
<https://github.com/SineSwiper/P9Y-ProcessTable/issues>.
AUTHOR
Brendan Byrd <bbyrd@cpan.org>
CONTRIBUTORS
* Brendan Byrd <GitHub@ResonatorSoft.org>
* Brendan Byrd <Perl@ResonatorSoft.org>
* Chris 'BinGOs' Williams <chris@bingosnet.co.uk>
* Mithun Ayachit <m0t0rbr3th@gmail.com>
* Mithun Ayachit <mayachit@amfam.com>
COPYRIGHT AND LICENSE
This software is Copyright (c) 2013 by Brendan Byrd.
This is free software, licensed under:
The Artistic License 2.0 (GPL Compatible)