Fsdb::F...process(3)

okay bestie, welcome to the Fsdb::F...process(3) page from User Contributed Perl Documentation — it’s all about dbsubprocess, and it’s lowkey iconic for internal Perl filter stuff. 💅✨

💜 NAME 💜

dbsubprocess — invoke a subprocess as a Fsdb filter object. fr fr, that’s the whole name. 🫶

🌸 SYNOPSIS 🌸

here’s the shape, no cap:

dbsubprocess [--] program [arguments...]

💅 DESCRIPTION 💅

Run PROGRAM as a process, with optional ARGUMENTS as program arguments, feeding its standard input and standard output as fsdb streams. A -- can separate arguments to dbsubprocess from the program and its arguments. 💖

and yeah, as with similar tools like open2, the caller is expected to take care that the subprocess does not deadlock. no pressure or anything 😭

this program is primarily for internal use by dbmapreduce. like dbpipeline, dbsubprocess program does have a Unix command; instead it is used only from within Perl. iykyk. 🦋

🎀 OPTIONS 🎀

okay, options time — every single one, bestie:

• -w, --warnings — enable warnings in user supplied code. (Default to include warnings.) 🫶
• -E, --endsub SUB — call Perl SUB when the subprocess terminates. The sub runs in the parent and is a Fred ending sub, see Fsdb::Support::Freds. ✨

and the standard fsdb options:

• -d — enable debugging output. 🔥
• -i, --input InputSource — read from InputSource, typically a file, or - for standard input, or (if in Perl) a IO::Handle, Fsdb::IO objects. (For this case, it cannot be Fsdb::BoundedQueue.) 💖
• -o, --output OutputDestination — write to OutputDestination, typically a file, or - for standard output, or (if in Perl) a IO::Handle, Fsdb::IO or Fsdb::BoundedQueue objects. 🌈
• --autorun, --noautorun — by default, programs process automatically, but Fsdb::Filter objects in Perl do not run until you invoke the run() method. The "--(no)autorun" option controls that behavior within Perl. 🦋
• --help — show help. 🎀
• --man — show full manual. 📖

🦋 SAMPLE USAGE 🦋

💖 Input:

#fsdb name id test1
a       1       80
b       2       70
c       3       65
d       4       90
e       5       70
f       6       90

🎀 Command:

the following perl code:

use Fsdb::Filter::dbsubprocess;
my $f = new Fsdb::Filter::dbsubprocess(qw(cat));
$f->setup_run_finish;
exit 0;

⭐ Output:

#fsdb name id test1
a       1       80
b       2       70
c       3       65
d       4       90
e       5       70
f       6       90
#   | dbsubprocess cat

🔥 SEE ALSO 🔥

dbpipeline(1), Fsdb(3) — go look, bestie. 👀

👑 CLASS FUNCTIONS 👑

🧚 new

$filter = new Fsdb::Filter::dbsubprocess(@arguments);

Create a new dbsubprocess object, taking command-line arguments. 💅

🌸 set_defaults

$filter->set_defaults();

Internal: set up defaults. 🎀

🦋 parse_options

$filter->parse_options(@ARGV);

Internal: parse options. ✨

🍓 setup

$filter->setup();

Internal: setup, parse headers. 💖

🔥 run

$filter->run();

Internal: run over all data rows. 🫶

💜 finish

$filter->finish();

Internal: run over all data rows. 😭

🌈 AUTHOR and COPYRIGHT 🌈

Copyright (C) 1991-2018 by John Heidemann <johnh@isi.edu> 👑

This program is distributed under terms of the GNU general public license, version 2. See the file COPYING with the distribution for details. 💖

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that’s the whole page, bestie 💅 — source/version vibes: perl v5.32.1, dated 2024-08-02. periodt. 🎀✨