Simple capturing of keyboard input without interruption Post: 303014186

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Top Forums Programming Simple capturing of keyboard input without interruption Post 303014186 by jim mcnamara on Tuesday 6th of March 2018 03:40:41 PM

03-06-2018

Registered User

Overview:
I'm not going to figure out all of the above wall of code. This example is how MS windows and X work. A simple, fairly stupid, event (message) pump that does nothing but read stdin, then send it off to a pipe. The little one I call "tiny" your code wall is "big" and it needs to dup() stdin on startup.

What you will do is to steal a tiny bit of windowing architecture - as in a message pump:
interpose a tiny program that loops and reads each character from stdin and then sends everything it gets from stdin to a pipe -except the <return> key. It exits or whatever you need on the return key.

Start the tiny program, have it fork your large program as a child that reads input from a pipe. Big's code can live in the same physical code that tiny lives in. Call fork() on the "big" entry point.

Tiny reads everything and simply passes it on, except in your case tiny exits when the ASCII 13 character (\n) is read. Tiny has almost zero smarts, just calls signal(), read(), wait() and pipe().

If tiny wants to quit: signal big, call wait() on big, then exit().
If big wants to quit: signal tiny, then exit() Tiny's signal handler gets the signal and exits.

If you really get stuck, post your attempt. If executable code lines in the tiny program code exceeds circa 50 lines or so your logic is probably too complex. Add bells and whistles after it works.

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LEARN ABOUT MOJAVE

module::build::tiny

Module::Build::Tiny(3pm)				User Contributed Perl Documentation				  Module::Build::Tiny(3pm)

NAME

       Module::Build::Tiny - A tiny replacement for Module::Build

VERSION

       version 0.034

SYNOPSIS

	use Module::Build::Tiny;
	Build_PL();

DESCRIPTION

       Many Perl distributions use a Build.PL file instead of a Makefile.PL file to drive distribution configuration, build, test and
       installation.  Traditionally, Build.PL uses Module::Build as the underlying build system.  This module provides a simple, lightweight,
       drop-in replacement.

       Whereas Module::Build has over 6,700 lines of code; this module has less than 120, yet supports the features needed by most distributions.

   Supported
       o   Pure Perl distributions

       o   Building XS or C

       o   Recursive test files

       o   MYMETA

       o   Man page generation

       o   Generated code from PL files

   Not Supported
       o   Dynamic prerequisites

       o   HTML documentation generation

       o   Extending Module::Build::Tiny

       o   Module sharedirs

   Directory structure
       Your .pm and .pod files must be in lib/.  Any executables must be in script/.  Test files must be in t/. Dist sharedirs must be in share/.

USAGE

       These all work pretty much like their Module::Build equivalents.

   perl Build.PL
   Build [ build ]
   Build test
   Build install
       This supports the following options:

       o   verbose

       o   install_base

       o   installdirs

       o   prefix

       o   install_path

       o   destdir

       o   uninst

       o   config

       o   pure-perl

       o   create_packlist

AUTHORING

       This module doesn't support authoring. To develop modules using Module::Build::Tiny, usage of Dist::Zilla::Plugin::ModuleBuildTiny or
       App::ModuleBuildTiny is recommended.

CONFIG FILE AND ENVIRONMENT

       Options can be provided in the "PERL_MB_OPT" environment variable the same way they can with Module::Build. This should be done during the
       configuration stage.

   Incompatibilities
       o   Argument parsing

	   Module::Build has an extremely permissive way of argument handling, Module::Build::Tiny only supports a (sane) subset of that. In
	   particular, "./Build destdir=/foo" does not work, you will need to pass it as "./Build --destdir=/foo".

       o   .modulebuildrc

	   Module::Build::Tiny does not support .modulebuildrc files. In particular, this means that versions of local::lib older than 1.006008
	   may break. Upgrading it resolves this issue.

SEE ALSO

       Module::Build

AUTHORS

       o   Leon Timmermans <leont@cpan.org>

       o   David Golden <dagolden@cpan.org>

COPYRIGHT AND LICENSE

       This software is copyright (c) 2011 by Leon Timmermans, David Golden.

       This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.

perl v5.18.2							    2014-01-21						  Module::Build::Tiny(3pm)

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