Front page | perl.perl6.users |
Postings from August 2018
RE: return code?
From: Mark Devine
August 10, 2018 02:18
RE: return code?
Message ID: BN6PR02MB27401034DAAA1D52586A35A5A0240@BN6PR02MB2740.namprd02.prod.outlook.com
I cleaned up my code and published it (with the help of Patrick Spek -- thanks again).
I’ve been using it in an enterprise environment with 1000+ UNIX/Linux servers. I’m able to launch hundreds of SSH commands at once and sort out each Proc::Async’s $*OUT and $*ERR without line noise. For version 0.0.2 I hardcoded a throttle of 16 threads after graphing performance on a 4 x Linux VM – seems safe yet efficient.
Criticisms & suggestions always welcome by Perl6 mentors.
From: Mark Devine <email@example.com>
Sent: Saturday, July 28, 2018 16:38
To: ToddAndMargo <ToddAndMargo@zoho.com>
Cc: perl6-users <firstname.lastname@example.org>
Subject: RE: return code?
I see that you’re frequently running commands in your code like me. I was looking for a reliable reusable approach for commands for a long time. I’m still learning & not quite ready to step up to contribute to the ecosystem yet (https://docs.perl6.org/language/modules.html). After reading Perl 6 Fundamentals (Moritz Lenz), I cobbled together a reusable Command.pm6 for myself based on his examples. Method ‘run’ for a single async command, or methods ‘sow’+‘reap’ for multiple async (possibly all different) commands, with all returns collected in Command::Result objects.
Now whenever I need any general-purpose external command, I ‘use Command;’ and it has never failed me (I.e. curl, , ssh, etc.).
Because it’s not in the ecosystem, git clone it into a directory and set PERL6LIB=<dir > or ‘use lib <dir>’ internally. Docs are internal POD.
If any of the Perl 6 big brains are reading this and would provide some welcome criticism resulting in something that should be published, I would upload as per the instructions it or hand it off to someone more capable of maintaining it.
If you give it a try, I think that you might find it helpful.
From: Brandon Allbery <email@example.com<mailto:firstname.lastname@example.org>>
Sent: Saturday, July 28, 2018 16:22
To: ToddAndMargo <ToddAndMargo@zoho.com<mailto:ToddAndMargo@zoho.com>>
Cc: perl6-users <email@example.com<mailto:firstname.lastname@example.org>>
Subject: Re: return code?
Yes, that's what I was addressing: you can tell run() to do that, keeping stderr separate with :err(). qxx does that internally.
On Sat, Jul 28, 2018 at 4:12 PM ToddAndMargo <ToddAndMargo@zoho.com<mailto:ToddAndMargo@zoho.com>> wrote:
On 07/28/2018 12:56 PM, Brandon Allbery wrote:
> You can control where run() sends things.
I adore the run command.
In this particular instance (curl's progress meter, which is
written to STDERR), I want STDERR to write to the shell, but
want to collect STDIN and the return code.
curl xxxx; echo $?
will send both to STDIN, which I can easily deal with.
brandon s allbery kf8nh sine nomine associates
unix, openafs, kerberos, infrastructure, xmonad http://sinenomine.net