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Term-Detect-Software-0.227
River stage two • 9 direct dependents • 65 total dependents
1 ++
/ Term::Detect::Software

NAME

Term::Detect::Software - Detect terminal (emulator) software and its capabilities

VERSION

This document describes version 0.227 of Term::Detect::Software (from Perl distribution Term-Detect-Software), released on 2024-02-10.

SYNOPSIS

 use Term::Detect::Software qw(detect_terminal detect_terminal_cached);
 my $res = detect_terminal();
 die "Not running under terminal!" unless $res->{emulator_engine};
 say "Emulator engine: ", $res->{emulator_engine};
 say "Emulator software: ", $res->{emulator_software};
 say "Unicode support? ", $res->{unicode} ? "yes":"no";
 say "Boxchars support? ", $res->{box_chars} ? "yes":"no";
 say "Color depth: ", $res->{color_depth};
 say "Inside emacs? ", $res->{inside_emacs} ? "yes":"no";

DESCRIPTION

This module uses several heuristics to find out what terminal (emulator) software the current process is running in, and its capabilities/settings. This module complements other modules such as Term::Terminfo and Term::Encoding.

FUNCTIONS

detect_terminal() => HASHREF

Return a hashref containing information about running terminal (emulator) software and its capabilities/settings.

Detection method is tried from the easiest/cheapest (e.g. checking environment variables) or by looking at known process names in the process tree. Terminal capabilities is determined using heuristics.

Currently Konsole and Konsole-based terminals (like Yakuake) can be detected through existence of environment variables KONSOLE_DBUS_SERVICE or KONSOLE_DBUS_SESSION. xterm is detected through XTERM_VERSION. XFCE's Terminal is detected using COLORTERM. The other software are detected via known process names.

Terminal capabilities and settings are currently determined via heuristics. Probing terminal configuration files might be performed in the future.

Result:

  • emulator_engine => STR

    Possible values: konsole, xterm, gnome-terminal, rxvt, pterm (PuTTY), xvt, windows (CMD.EXE), cygwin, st (suckless.org's terminal emulator), or empty string (if not detected running under terminal).

  • emulator_software => STR

    Either: xfce4-terminal, guake, gnome-terminal, mlterm, lxterminal, rxvt, mrxvt, putty, xvt, windows (CMD.EXE), st (suckless.org's terminal emulator), or empty string (if not detected running under terminal).

  • color_depth => INT

    Either 0 (does not support ANSI color codes), 16, 256, or 16777216 (2**24).

  • default_bgcolor => STR (6-hexdigit RGB)

    For example, any xterm is assumed to have white background (ffffff) by default, while Konsole is assumed to have black (000000). Better heuristics will be done in the future.

  • unicode => BOOL

    Whether terminal software supports Unicode/wide characters. Note that you should also check encoding, e.g. using Term::Encoding.

  • box_chars => BOOL

    Whether terminal supports box-drawing characters.

detect_terminal_cached([$flag]) => ANY

Just like detect_terminal() but will cache the result. Can be used by applications or modules to avoid repeating detection process.

FAQ

What is this module for? Why not Term::Terminfo or Term::Encoding?

This module was first written for Text::ANSITable so that the latter can provide good defaults when displaying formatted and colored tables, especially on popular terminal emulation software like Konsole (KDE's default terminal), gnome-terminal (GNOME's default), Terminal (XFCE's default), xterm, rxvt.

This module works by trying to figure out the terminal emulation software because the information provided by Term::Terminfo and Term::Encoding are sometimes not specific enough. For example, Term::Encoding can return utf-8 when running under rxvt, but since the software currently lacks Unicode support we shouldn't display Unicode characters. Another example is color depth: Term::Terminfo currently doesn't recognize Konsole's 24bit color support and only gives max_colors 256.

Which terminal software are detected?

See "PERL_TERM_DETECT_SOFTWARE_ENGINE".

Why is my terminal software not detected?

By default, some software are not detected because the heuristics to do so is considered rather costly. This includes detecting gnome-terminal, rxvt, mrxvt, st, pterm/putty, xvt via checking process name, because listing all processes and their details costs tens to hundreds of milliseconds. See "PERL_TERM_DETECT_SOFTWARE_CHECK_PS" to enable it.

ENVIRONMENT

PERL_TERM_DETECT_SOFTWARE_CHECK_PS

By default, some software are not detected because the heuristics to do so is considered rather costly. This includes detecting gnome-terminal, rxvt, mrxvt, st, pterm/putty, xvt via checking process name, because listing all processes and their details costs tens to hundreds of milliseconds. To enable this checking, set this environment variable to true and install the optional dependency Proc::Find::Parents.

PERL_TERM_DETECT_SOFTWARE_ENGINE

String. Explicitly instruct Term::Detect::Software to use a specific engine, instead of heuristically trying to detect. This is useful for testing or for avoiding sometimes costly detection.

List of supported engines:

 konsole
 xterm
 cygwin
 linux            # linux virtual console
 gnome-terminal
 windows          # windows command prompt
 dumb             # dumb/generic, e.g. run under CGI or something like that
 rxvt
 st
 putty
 xvt

For more details on the capabilities of each engine, currently please peruse the source code.

HOMEPAGE

Please visit the project's homepage at https://metacpan.org/release/Term-Detect-Software.

SOURCE

Source repository is at https://github.com/perlancar/perl-Term-Detect-Software.

SEE ALSO

Term::Terminfo

Term::Encoding

AUTHOR

perlancar <perlancar@cpan.org>

CONTRIBUTOR

Steven Haryanto <stevenharyanto@gmail.com>

CONTRIBUTING

To contribute, you can send patches by email/via RT, or send pull requests on GitHub.

Most of the time, you don't need to build the distribution yourself. You can simply modify the code, then test via:

 % prove -l

If you want to build the distribution (e.g. to try to install it locally on your system), you can install Dist::Zilla, Dist::Zilla::PluginBundle::Author::PERLANCAR, Pod::Weaver::PluginBundle::Author::PERLANCAR, and sometimes one or two other Dist::Zilla- and/or Pod::Weaver plugins. Any additional steps required beyond that are considered a bug and can be reported to me.

COPYRIGHT AND LICENSE

This software is copyright (c) 2024, 2023, 2020, 2019, 2015, 2014, 2013 by perlancar <perlancar@cpan.org>.

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

BUGS

Please report any bugs or feature requests on the bugtracker website https://rt.cpan.org/Public/Dist/Display.html?Name=Term-Detect-Software

When submitting a bug or request, please include a test-file or a patch to an existing test-file that illustrates the bug or desired feature.