term(7)                                                   term(7)

     NAME      term - conventions for naming terminal types

     DESCRIPTION

          The environment variable TERM should normally contain the
          type name of the terminal, console or display-device type
          you are using.  This information is critical for all
          screen-oriented programs, including your editor and mailer.

          A default TERM value will be set on a per-line basis by
          either /etc/inittab (e.g., System-V-like UNIXes) or
          /etc/ttys (BSD UNIXes).  This will nearly always suffice for
          workstation and microcomputer consoles.

          If you use a dialup line, the type of device attached to it
          may vary.  Older UNIX systems pre-set a very dumb terminal
          type like ``dumb'' or ``dialup'' on dialup lines.  Newer
          ones may pre-set ``vt100'', reflecting the prevalence of DEC
          VT100-compatible terminals and personal-computer emulators.

          Modern telnets pass your TERM environment variable from the
          local side to the remote one.  There can be problems if the
          remote terminfo or termcap entry for your type is not
          compatible with yours, but this situation is rare and can
          almost always be avoided by explicitly exporting ``vt100''
          (assuming you are in fact using a VT100-superset console,
          terminal, or terminal emulator.)

          In any case, you are free to override the system TERM
          setting to your taste in your shell profile.  The tset(1)
          utility may be of assistance; you can give it a set of rules
          for deducing or requesting a terminal type based on the tty
          device and baud rate.

          Setting your own TERM value may also be useful if you have
          created a custom entry incorporating options (such as visual
          bell or reverse-video) which you wish to override the system
          default type for your line.

          Terminal type descriptions are stored as files of capability
          data underneath /etc/terminfo.  To browse a list of all
          terminal names recognized by the system, do

               toe | more

          from your shell.  These capability files are in a binary
          format optimized for retrieval speed (unlike the old text-
          based termcap format they replace); to examine an entry, you
          must use the infocmp(1) command.  Invoke it as follows:

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     term(7)                                                   term(7)

               infocmp entry_name

          where entry_name is the name of the type you wish to examine
          (and the name of its capability file the subdirectory of
          /etc/terminfo named for its first letter).  This command
          dumps a capability file in the text format described by
          terminfo(5).

          The first line of a terminfo(5) description gives the names
          by which terminfo knows a terminal, separated by ``|''
          (pipe-bar) characters with the last name field terminated by
          a comma.  The first name field is the type's primary name,
          and is the one to use when setting TERM.  The last name
          field (if distinct from the first) is actually a description
          of the terminal type (it may contain blanks; the others must
          be single words).  Name fields between the first and last
          (if present) are aliases for the terminal, usually
          historical names retained for compatibility.

          There are some conventions for how to choose terminal
          primary names that help keep them informative and unique.
          Here is a step-by-step guide to naming terminals that also
          explains how to parse them:

          First, choose a root name.  The root will consist of a
          lower-case letter followed by up to seven lower-case letters
          or digits.  You need to avoid using punctuation characters
          in root names, because they are used and interpreted as
          filenames and shell meta-characters (such as !, $, *, ?,
          etc.) embedded in them may cause odd and unhelpful behavior.
          The slash (/), or any other character that may be
          interpreted by anyone's file system (\, $, [, ]), is
          especially dangerous (terminfo is platform-independent, and
          choosing names with special characters could someday make
          life difficult for users of a future port).  The dot (.)
          character is relatively safe as long as there is at most one
          per root name; some historical terminfo names use it.

          The root name for a terminal or workstation console type
          should almost always begin with a vendor prefix (such as hp
          for Hewlett-Packard, wy for Wyse, or att for AT&T
          terminals), or a common name of the terminal line (vt for
          the VT series of terminals from DEC, or sun for Sun
          Microsystems workstation consoles, or regent for the ADDS
          Regent series.  You can list the terminfo tree to see what
          prefixes are already in common use.  The root name prefix
          should be followed when appropriate by a model number; thus
          vt100, hp2621, wy50.

          The root name for a PC-Unix console type should be the OS
          name, i.e., linux, bsdos, freebsd, netbsd.  It should not be
          console or any other generic that might cause confusion in a

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     term(7)                                                   term(7)

          multi-platform environment!  If a model number follows, it
          should indicate either the OS release level or the console
          driver release level.

          The root name for a terminal emulator (assuming it does not
          fit one of the standard ANSI or vt100 types) should be the
          program name or a readily recognizable abbreviation of it
          (i.e., versaterm, ctrm).

          Following the root name, you may add any reasonable number
          of hyphen-separated feature suffixes.

          2p   Has two pages of memory.  Likewise 4p, 8p, etc.

          mc   Magic-cookie.  Some terminals (notably older Wyses) can
               only support one attribute without magic-cookie
               lossage.  Their base entry is usually paired with
               another that has this suffix and uses magic cookies to
               support multiple attributes.

          -am  Enable auto-margin (right-margin wraparound).

          -m   Mono mode - suppress color support.

          -na  No arrow keys - termcap ignores arrow keys which are
               actually there on the terminal, so the user can use the
               arrow keys locally.

          -nam No auto-margin - suppress am capability.

          -nl  No labels - suppress soft labels.

          -nsl No status line - suppress status line.

          -pp  Has a printer port which is used.

          -rv  Terminal in reverse video mode (black on white).

          -s   Enable status line.

          -vb  Use visible bell (flash) rather than beep.

          -w   Wide; terminal is in 132-column mode.

          Conventionally, if your terminal type is a variant intended
          to specify a line height, that suffix should go first.  So,
          for a hypothetical FuBarCo model 2317 terminal in 30-line
          mode with reverse video, best form would be fubar-30-rv
          (rather than, say, ``fubar-rv-30'').

          Terminal types that are written not as standalone entries,
          but rather as components to be plugged into other entries

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     term(7)                                                   term(7)

          via use capabilities, are distinguished by using embedded
          plus signs rather than dashes.

          Commands which use a terminal type to control display often
          accept a -T option that accepts a terminal name argument.
          Such programs should fall back on the TERM environment
          variable when no -T option is specified.

     PORTABILITY      For maximum compatibility with older System V
          UNIXes, names and aliases should be unique within the first
          14 characters.

     FILES

          /etc/terminfo/?/*
               compiled terminal capability data base

          /etc/inittab
               tty line initialization (AT&T-like UNIXes)

          /etc/ttys
               tty line initialization (BSD-like UNIXes)

     SEE ALSO     ncurses(3NCURSES), terminfo(5), term(5).

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