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curses(3X)

infocmp(1M)

terminfo(4)

term(5)



term(4)                   FILE FORMATS                    term(4)



NAME
     term - format of compiled term file

SYNOPSIS
     /usr/share/lib/terminfo/?/*

DESCRIPTION
     Compiled  terminfo(4)  descriptions  are  placed  under  the
     directory  /usr/share/lib/terminfo.   In  order  to  avoid a
     linear search of a huge UNIX system directory,  a  two-level
     scheme  is  used:  /usr/share/lib/terminfo/c/name where name
     is the name of the terminal, and c is the first character of
     name.    Thus,   att4425   can   be   found   in   the  file
     /usr/share/lib/terminfo/a/att4425.  Synonyms  for  the  same
     terminal  are implemented by multiple links to the same com-
     piled file.

     The format has been chosen so that it is  the  same  on  all
     hardware.   An  8-bit  byte  is  assumed, but no assumptions
     about byte ordering or sign extension are made.  Thus, these
     binary  terminfo  files can be transported to other hardware
     with 8-bit bytes.

     Short integers are stored in two  8-bit  bytes.   The  first
     byte contains the least significant 8 bits of the value, and
     the second  byte  contains  the  most  significant  8  bits.
     (Thus,  the  value  represented  is  256*second+first.)  The
     value -1 is represented by 0377,0377, and the  value  -2  is
     represented by 0376,0377; other negative values are illegal.
     The -1 generally means that a  capability  is  missing  from
     this  terminal.   The  -2 means that the capability has been
     cancelled in the terminfo source and  also  is  to  be  con-
     sidered missing.

     The compiled file is created from the source  file  descrip-
     tions  of  the  terminals  (see the -I option of infocmp) by
     using the terminfo compiler, tic, and read  by  the  routine
     setupterm  [see  curses(3X).]   The file is divided into six
     parts in the following order:  the header,  terminal  names,
     boolean flags, numbers, strings, and string table.

     The header section begins the file.  This  section  contains
     six  short  integers  in  the format described below.  These
     integers are (1) the magic  number  (octal  0432);  (2)  the
     size,  in  bytes,  of  the  names section; (3) the number of
     bytes in the  boolean  section;  (4)  the  number  of  short
     integers  in  the numbers section; (5) the number of offsets
     (short integers) in the strings section; (6)  the  size,  in
     bytes, of the string table.

     The terminal names section  comes  next.   It  contains  the
     first  line of the terminfo description, listing the various



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term(4)                   FILE FORMATS                    term(4)



     names for the terminal, separated by the bar ( | ) character
     (see  term(5)).  The section is terminated with an ASCII NUL
     character.

     The boolean flags have one byte for each flag.  This byte is
     either  0  or 1 as the flag is present or absent.  The value
     of 2 means that the flag has been cancelled.  The  capabili-
     ties are in the same order as the file <term.h>.

     Between the boolean section and the number section,  a  null
     byte  is  inserted,  if necessary, to ensure that the number
     section begins on an even byte offset.  All  short  integers
     are aligned on a short word boundary.

     The numbers section is similar to the boolean flags section.
     Each capability takes up two bytes, and is stored as a short
     integer.  If the value represented is -1 or -2, the capabil-
     ity is taken to be missing.

     The strings section is also  similar.   Each  capability  is
     stored  as a short integer, in the format above.  A value of
     -1 or -2 means the capability is  missing.   Otherwise,  the
     value is taken as an offset from the beginning of the string
     table.  Special characters in ^X or \c notation  are  stored
     in  their interpreted form, not the printing representation.
     Padding information ($<nn>) and parameter  information  (%x)
     are stored intact in uninterpreted form.

     The final section is the string table.  It contains all  the
     values  of string capabilities referenced in the string sec-
     tion.  Each string is null terminated.

     Note that it is possible for setupterm to expect a different
     set  of  capabilities than are actually present in the file.
     Either the database may have been  updated  since  setupterm
     has been recompiled (resulting in extra unrecognized entries
     in the file) or the program may have  been  recompiled  more
     recently than the database was updated (resulting in missing
     entries).  The routine setupterm must be prepared  for  both
     possibilities-this   is   why  the  numbers  and  sizes  are
     included.  Also, new capabilities must always  be  added  at
     the end of the lists of boolean, number, and string capabil-
     ities.

     As an example, here is  terminal  information  on  the  AT&T
     Model 37 KSR terminal as output by the infocmp -I tty37 com-
     mand:

          37|tty37|AT&T model 37 teletype,
            hc, os, xon,
            bel=^G, cr=\r, cub1=\b, cud1=\n, cuu1=\E7, hd=\E9,
            hu=\E8, ind=\n,



                                                                2





term(4)                   FILE FORMATS                    term(4)



     And here is an octal dump of the term file, produced by  the
     od -c /usr/share/lib/terminfo/t/tty37 command:
     0000000 032 001      \0 032  \0 013  \0 021 001   3  \0   3   7   |   t
     0000020   t   y   3   7   |   A   T   &   T       m   o   d   e   l
     0000040   3   7       t   e   l   e   t   y   p   e  \0  \0  \0  \0  \0
     0000060  \0  \0  \0 001  \0  \0  \0  \0  \0  \0  \0 001  \0  \0  \0  \0
     0000100 001  \0  \0  \0  \0  \0 377 377 377 377 377 377 377 377 377 377
     0000120 377 377 377 377 377 377 377 377 377 377 377 377 377 377   &  \0
     0000140      \0 377 377 377 377 377 377 377 377 377 377 377 377 377 377
     0000160 377 377   "  \0 377 377 377 377   (  \0 377 377 377 377 377 377
     0000200 377 377   0  \0 377 377 377 377 377 377 377 377   -  \0 377 377
     0000220 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377
     *
     0000520 377 377 377 377 377 377 377 377 377 377 377 377 377 377   $  \0
     0000540 377 377 377 377 377 377 377 377 377 377 377 377 377 377   *  \0
     0000560 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377 377
     *
     0001160 377 377 377 377 377 377 377 377 377 377 377 377 377 377   3   7
     0001200   |   t   t   y   3   7   |   A   T   &   T       m   o   d   e
     0001220   l       3   7       t   e   l   e   t   y   p   e  \0  \r  \0
     0001240  \n  \0  \n  \0 007  \0  \b  \0 033   8  \0 033   9  \0 033   7
     0001260  \0  \0
     0001261

     Some limitations: total compiled entries cannot exceed  4096
     bytes;  all  entries  in  the  name  field cannot exceed 128
     bytes.

FILES
     /usr/share/lib/terminfo/?/*compiled   terminal   description
     database
     /usr/include/term.hterminfo header file

SEE ALSO
     curses(3X).
     infocmp(1M), terminfo(4), term(5)



















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Typewritten Software • bear@typewritten.org • Edmonds, WA 98026