term_variables(3x) — Linux manual page


term_variables(3X)                                    term_variables(3X)

NAME         top

       SP, acs_map, boolcodes, boolfnames, boolnames, cur_term,
       numcodes, numfnames, numnames, strcodes, strfnames, strnames,
       ttytype - curses terminfo global variables

SYNOPSIS         top

       #include <curses.h>
       #include <term.h>

       chtype acs_map[];

       SCREEN * SP;

       TERMINAL * cur_term;

       char ttytype[];

       NCURSES_CONST char * const boolcodes[];
       NCURSES_CONST char * const boolfnames[];
       NCURSES_CONST char * const boolnames[];

       NCURSES_CONST char * const numcodes[];
       NCURSES_CONST char * const numfnames[];
       NCURSES_CONST char * const numnames[];

       NCURSES_CONST char * const strcodes[];
       NCURSES_CONST char * const strfnames[];
       NCURSES_CONST char * const strnames[];

DESCRIPTION         top

       This  page  summarizes variables provided by the curses library's
       low-level terminfo interface.  A  more  complete  description  is
       given in the curs_terminfo(3X) manual page.

       Depending on the configuration, these may be actual variables, or
       macros  (see  curs_threads(3X)) which provide read-only access to
       curses's state.  In either case, applications should  treat  them
       as read-only to avoid confusing the library.

   Alternate Character Set Mapping
       After initializing the curses or terminfo interfaces, the acs_map
       array   holds  information  used  to  translate  cells  with  the
       A_ALTCHARSET video attribute into line-drawing characters.

       The encoding of the information in this array has changed period‐
       ically.  Application developers need only know that  it  is  used
       for the “ACS_” constants in <curses.h>.

       The  comparable  data for the wide-character library is a private

   Current Terminal Data
       After  initializing  the  curses  or  terminfo  interfaces,   the
       cur_term  contains  data  describing  the current terminal.  This
       variable is  also  set  as  a  side-effect  of  set_term(3X)  and

       It  is possible to save a value of cur_term for subsequent use as
       a parameter to set_term, for switching between screens.  Alterna‐
       tively, one can  save  the  return  value  from  newterm  or  se‐
       tupterm(3X) to reuse in set_term.

   Terminfo Lookup Tables
       The  @TIC@(1) and @INFOCMP@(1) programs use lookup tables for the
       long and short names of terminfo capabilities,  as  well  as  the
       corresponding  names  for termcap capabilities.  These are avail‐
       able to other applications, although the hash-tables used by  the
       terminfo and termcap functions are not available.

       The  long  terminfo  capability  names  use  a “f” (eff) in their
       names: boolfnames, numfnames, and strfnames.

       These are the short names for terminfo  capabilities:  boolnames,
       numnames, and strnames.

       These  are the corresponding names used for termcap descriptions:
       boolcodes, numcodes, and strcodes.

   Terminal Type
       A terminal description begins with one  or  more  terminal  names
       separated by “|” (vertical bars).  On initialization of the curs‐
       es  or  terminfo  interfaces,  setupterm(3X)  copies the terminal
       names to the array ttytype.

   Terminfo Names
       In addition to the variables, <term.h> also defines a symbol  for
       each  terminfo  capability  long name.  These are in terms of the
       symbol CUR, which is defined

       #define CUR ((TERMTYPE *)(cur_term))->

       These symbols provide a faster method of accessing terminfo capa‐
       bilities than using tigetstr(3X), etc.

       The actual definition of CUR depends upon the implementation, but
       each terminfo library provides these long names defined to  point
       into the current terminal description loaded into memory.

NOTES         top

       The   low-level   terminfo   interface   is   initialized   using
       setupterm(3X).  The upper-level curses interface  uses  the  low-
       level terminfo interface, internally.

PORTABILITY         top

       X/Open Curses does not describe any of these except for cur_term.
       (The inclusion of cur_term appears to be an oversight, since oth‐
       er comparable low-level information is omitted by X/Open).

       Other implementations may have comparable variables.  Some imple‐
       mentations  provide  the  variables  in their libraries, but omit
       them from the header files.

       All implementations which provide terminfo interfaces add defini‐
       tions as described in the Terminfo Names section.  Most, but  not
       all, base the definition upon the cur_term variable.

SEE ALSO         top

       curses(3X), curs_terminfo(3X), curs_threads(3X), terminfo(5).

COLOPHON         top

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