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.

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.

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.