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term(5)                                          File Formats Manual                                          term(5)



NAME
       term - format of compiled term file.

SYNOPSIS
       term

DESCRIPTION
   STORAGE LOCATION
       Compiled  terminfo  descriptions  are  placed under the directory /usr/share/terminfo.  Two configurations are
       supported (when building the ncurses libraries):

       directory tree
            A two-level scheme is used to avoid a linear search of a  huge  UNIX  system  directory:  /usr/share/ter‐
            minfo/c/name  where  name  is the name of the terminal, and c is the first character of name.  Thus, act4
            can be found in the file /usr/share/terminfo/a/act4.  Synonyms for the same terminal are  implemented  by
            multiple links to the same compiled file.

       hashed database
            Using  Berkeley database, two types of records are stored: the terminfo data in the same format as stored
            in a directory tree with the terminfo's primary name as a key, and records containing only aliases point‐
            ing to the primary name.

            If  built  to  write hashed databases, ncurses can still read terminfo databases organized as a directory
            tree, but cannot write entries into the directory tree.  It can write (or rewrite) entries in the  hashed
            database.

            ncurses  distinguishes the two cases in the TERMINFO and TERMINFO_DIRS environment variable by assuming a
            directory tree for entries that correspond to an existing directory, and hashed database otherwise.

   STORAGE FORMAT
       The format has been chosen so that it will be the same on all hardware.  An 8 or more bit byte is assumed, but
       no assumptions about byte ordering or sign extension are made.

       The  compiled  file  is  created with the tic program, and read by the routine setupterm.  The file is divided
       into six parts: 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.

       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*sec‐
       ond+first.)   The value -1 is represented by the two bytes 0377, 0377; other negative values are illegal. This
       value generally means that the corresponding capability is missing from this terminal.  Note that this  format
       corresponds to the hardware of the VAX and PDP-11 (that is, little-endian machines).  Machines where this does
       gers are aligned on a short word boundary.

       The numbers section is similar to the flags section.  Each capability takes up two bytes, and is stored  as  a
       little-endian short integer.  If the value represented is -1, the capability 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 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 uninter‐
       preted form.

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

   EXTENDED STORAGE FORMAT
       The previous section describes the conventional terminfo binary format.  With some  minor  variations  of  the
       offsets (see PORTABILITY), the same binary format is used in all modern UNIX systems.  Each system uses a pre‐
       defined set of boolean, number or string capabilities.

       The ncurses libraries and applications support extended terminfo binary format, allowing users to define capa‐
       bilities which are loaded at runtime.  This extension is made possible by using the fact that the other imple‐
       mentations stop reading the terminfo data when they have reached the end of the  size  given  in  the  header.
       ncurses  checks  the  size, and if it exceeds that due to the predefined data, continues to parse according to
       its own scheme.

       First, it reads the extended header (5 short integers):

            (1)  count of extended boolean capabilities

            (2)  count of extended numeric capabilities

            (3)  count of extended string capabilities

            (4)  size of the extended string table in bytes.

            (5)  last offset of the extended string table in bytes.

       Using the counts and sizes, ncurses allocates arrays and reads data for the extended capabilties in  the  same
       order as the header information.

       The extended string table contains values for string capabilities.  After the end of these values, it contains
       the names for each of the extended capabilities in order, e.g., booleans, then numbers and finally strings.

PORTABILITY
       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 capabilities.

       Despite  the  consistent  use of little-endian for numbers and the otherwise self-describing format, it is not
       wise to count on portability of binary terminfo entries between commercial UNIX versions.  The problem is that
       there  are at least three versions of terminfo (under HP-UX, AIX, and OSF/1) which diverged from System V ter‐

               cuf1=^L, cup=\E=%p1%{32}%+%c%p2%{32}%+%c, cuu1=^K,
               home=^^, ind=^J,

       0000  1a 01 10 00 02 00 03 00  82 00 31 00 61 64 6d 33  ........ ..1.adm3
       0010  61 7c 6c 73 69 20 61 64  6d 33 61 00 00 01 50 00  a|lsi ad m3a...P.
       0020  ff ff 18 00 ff ff 00 00  02 00 ff ff ff ff 04 00  ........ ........
       0030  ff ff ff ff ff ff ff ff  0a 00 25 00 27 00 ff ff  ........ ..%.'...
       0040  29 00 ff ff ff ff 2b 00  ff ff 2d 00 ff ff ff ff  ).....+. ..-.....
       0050  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  ........ ........
       0060  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  ........ ........
       0070  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  ........ ........
       0080  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  ........ ........
       0090  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  ........ ........
       00a0  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  ........ ........
       00b0  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  ........ ........
       00c0  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  ........ ........
       00d0  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  ........ ........
       00e0  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  ........ ........
       00f0  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  ........ ........
       0100  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  ........ ........
       0110  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  ........ ........
       0120  ff ff ff ff ff ff 2f 00  07 00 0d 00 1a 24 3c 31  ....../. .....$<1
       0130  3e 00 1b 3d 25 70 31 25  7b 33 32 7d 25 2b 25 63  >..=%p1% {32}%+%c
       0140  25 70 32 25 7b 33 32 7d  25 2b 25 63 00 0a 00 1e  %p2%{32} %+%c....
       0150  00 08 00 0c 00 0b 00 0a  00                       ........ .


LIMITS
       Some limitations: total compiled entries cannot exceed 4096 bytes.  The name field cannot exceed 128 bytes.

FILES
       /usr/share/terminfo/*/*  compiled terminal capability data base

SEE ALSO
       curses(3X), terminfo(5).

AUTHORS
       Thomas E. Dickey
       extended terminfo format for ncurses 5.0
       hashed database support for ncurses 5.6

       Eric S. Raymond



                                                                                                              term(5)