1 .\"***************************************************************************
2 .\" Copyright (c) 1998-2018,2019 Free Software Foundation, Inc. *
4 .\" Permission is hereby granted, free of charge, to any person obtaining a *
5 .\" copy of this software and associated documentation files (the *
6 .\" "Software"), to deal in the Software without restriction, including *
7 .\" without limitation the rights to use, copy, modify, merge, publish, *
8 .\" distribute, distribute with modifications, sublicense, and/or sell *
9 .\" copies of the Software, and to permit persons to whom the Software is *
10 .\" furnished to do so, subject to the following conditions: *
12 .\" The above copyright notice and this permission notice shall be included *
13 .\" in all copies or substantial portions of the Software. *
15 .\" THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS *
16 .\" OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF *
17 .\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. *
18 .\" IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, *
19 .\" DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR *
20 .\" OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR *
21 .\" THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
23 .\" Except as contained in this notice, the name(s) of the above copyright *
24 .\" holders shall not be used in advertising or otherwise to promote the *
25 .\" sale, use or other dealings in this Software without prior written *
27 .\"***************************************************************************
29 .\" $Id: term.5,v 1.32 2019/01/12 23:11:08 tom Exp $
56 term \- format of compiled term file.
61 Compiled terminfo descriptions are placed under the directory \fB\*d\fP.
62 Two configurations are supported (when building the \fBncurses\fP libraries):
65 A two-level scheme is used to avoid a linear search
66 of a huge \s-1UNIX\s+1 system directory: \fB\*d/c/name\fP where
68 is the name of the terminal, and
70 is the first character of
74 can be found in the file \fB\*d/a/act4\fP.
75 Synonyms for the same terminal are implemented by multiple
76 links to the same compiled file.
79 Using Berkeley database, two types of records are stored:
80 the terminfo data in the same format as stored in a directory tree with
81 the terminfo's primary name as a key,
82 and records containing only aliases pointing to the primary name.
84 If built to write hashed databases,
85 \fBncurses\fP can still read terminfo databases organized as a directory tree,
86 but cannot write entries into the directory tree.
87 It can write (or rewrite) entries in the hashed database.
89 \fBncurses\fP distinguishes the two cases in the TERMINFO and TERMINFO_DIRS
90 environment variable by assuming a directory tree for entries that
91 correspond to an existing directory,
92 and hashed database otherwise.
93 .SS LEGACY STORAGE FORMAT
94 The format has been chosen so that it will be the same on all hardware.
95 An 8 or more bit byte is assumed, but no assumptions about byte ordering
96 or sign extension are made.
98 The compiled file is created with the \fB@TIC@\fP program,
99 and read by the routine \fBsetupterm\fP(3X).
100 The file is divided into six parts:
109 The header section begins the file.
110 This section contains six short integers in the format
115 (1) the magic number (octal 0432);
117 (2) the size, in bytes, of the names section;
119 (3) the number of bytes in the boolean section;
121 (4) the number of short integers in the numbers section;
123 (5) the number of offsets (short integers) in the strings section;
125 (6) the size, in bytes, of the string table.
128 Short integers are stored in two 8-bit bytes.
129 The first byte contains the least significant 8 bits of the value,
130 and the second byte contains the most significant 8 bits.
131 (Thus, the value represented is 256*second+first.)
132 The value \-1 is represented by the two bytes 0377, 0377; other negative
135 means that the corresponding capability is missing from this terminal.
136 Note that this format corresponds to the hardware of the \s-1VAX\s+1
137 and \s-1PDP\s+1-11 (that is, little-endian machines).
138 Machines where this does not correspond to the hardware must read the
139 integers as two bytes and compute the little-endian value.
141 The terminal names section comes next.
142 It contains the first line of the terminfo description,
143 listing the various names for the terminal,
144 separated by the \*(``|\*('' character.
145 The section is terminated with an \s-1ASCII NUL\s+1 character.
147 The boolean flags have one byte for each flag.
148 This byte is either 0 or 1 as the flag is present or absent.
149 The capabilities are in the same order as the file <term.h>.
151 Between the boolean section and the number section,
152 a null byte will be inserted, if necessary,
153 to ensure that the number section begins on an even byte (this is a
154 relic of the PDP\-11's word-addressed architecture, originally
155 designed in to avoid IOT traps induced by addressing a word on an
157 All short integers are aligned on a short word boundary.
159 The numbers section is similar to the flags section.
160 Each capability takes up two bytes,
161 and is stored as a little-endian short integer.
162 If the value represented is \-1, the capability is taken to be missing.
164 The strings section is also similar.
165 Each capability is stored as a short integer, in the format above.
166 A value of \-1 means the capability is missing.
167 Otherwise, the value is taken as an offset from the beginning
169 Special characters in ^X or \ec notation are stored in their
170 interpreted form, not the printing representation.
171 Padding information $<nn> and parameter information %x are
172 stored intact in uninterpreted form.
174 The final section is the string table.
175 It contains all the values of string capabilities referenced in
177 Each string is null terminated.
178 .SS EXTENDED STORAGE FORMAT
179 The previous section describes the conventional terminfo binary format.
180 With some minor variations of the offsets (see PORTABILITY),
181 the same binary format is used in all modern UNIX systems.
182 Each system uses a predefined set of boolean, number or string capabilities.
184 The \fBncurses\fP libraries and applications support
185 extended terminfo binary format,
186 allowing users to define capabilities which are loaded at runtime.
188 extension is made possible by using the fact that the other implementations
189 stop reading the terminfo data when they have reached the end of the size given
191 \fBncurses\fP checks the size,
192 and if it exceeds that due to the predefined data,
193 continues to parse according to its own scheme.
195 First, it reads the extended header (5 short integers):
199 count of extended boolean capabilities
202 count of extended numeric capabilities
205 count of extended string capabilities
208 count of the items in extended string table
211 size of the extended string table in bytes
214 The count- and size-values for the extended string table
215 include the extended capability \fInames\fP as well as
216 extended capability \fIvalues\fP.
218 Using the counts and sizes, \fBncurses\fP allocates arrays and reads data
219 for the extended capabilities in the same order as the header information.
221 The extended string table contains values for string capabilities.
222 After the end of these values, it contains the names for each of
223 the extended capabilities in order, e.g., booleans, then numbers and
226 Applications which manipulate terminal data can use the definitions
227 described in \fBterm_variables\fP(3X) which associate the long capability
228 names with members of a \fBTERMTYPE\fP structure.
230 .SS EXTENDED NUMBER FORMAT
232 On occasion, 16-bit signed integers are not large enough.
233 With \fBncurses\fP 6.1, a new format was introduced by making a few changes
234 to the legacy format:
236 a different magic number (octal 01036)
238 changing the type for the \fInumber\fP array from signed 16-bit integers
239 to signed 32-bit integers.
241 To maintain compatibility, the library presents the same data structures
242 to direct users of the \fBTERMTYPE\fP structure as in previous formats.
243 However, that cannot provide callers with the extended numbers.
244 The library uses a similar but hidden data structure \fBTERMTYPE2\fP
245 to provide data for the terminfo functions.
249 Note that it is possible for
251 to expect a different set of capabilities
252 than are actually present in the file.
253 Either the database may have been updated since
256 (resulting in extra unrecognized entries in the file)
257 or the program may have been recompiled more recently
258 than the database was updated
259 (resulting in missing entries).
262 must be prepared for both possibilities \-
263 this is why the numbers and sizes are included.
264 Also, new capabilities must always be added at the end of the lists
265 of boolean, number, and string capabilities.
268 X/Open Curses does not specify a format for the terminfo database.
269 UNIX System V curses used a directory-tree of binary files,
270 one per terminal description.
272 Despite the consistent use of little-endian for numbers and the otherwise
273 self-describing format, it is not wise to count on portability of binary
274 terminfo entries between commercial UNIX versions.
275 The problem is that there
276 are at least three versions of terminfo (under HP\-UX, AIX, and OSF/1) which
277 diverged from System V terminfo after SVr1, and have added extension
278 capabilities to the string table that (in the binary format) collide with
279 System V and XSI Curses extensions.
280 See \fBterminfo\fR(\*n) for detailed
281 discussion of terminfo source compatibility issues.
283 This implementation is by default compatible with the binary
284 terminfo format used by Solaris curses,
285 except in a few less-used details
286 where it was found that the latter did not match X/Open Curses.
287 The format used by the other Unix versions
288 can be matched by building ncurses
289 with different configuration options.
292 The magic number in a binary terminfo file is the first 16-bits (two bytes).
293 Besides making it more reliable for the library to check that a file
295 utilities such as \fBfile\fP also use that to tell what the file-format is.
296 System V defined more than one magic number,
297 with 0433, 0435 as screen-dumps (see \fBscr_dump\fP(5)).
298 This implementation uses 01036 as a continuation of that sequence,
299 but with a different high-order byte to avoid confusion.
300 .SS The TERMTYPE structure
302 Direct access to the \fBTERMTYPE\fP structure is provided for legacy
304 Portable applications should use the \fBtigetflag\fP and related functions
305 described in \fBcurs_terminfo\fP(3X) for reading terminal capabilities.
306 .SS Mixed-case terminal names
308 A small number of terminal descriptions use uppercase characters in
310 If the underlying filesystem ignores the difference between
311 uppercase and lowercase,
312 \fBncurses\fP represents the \*(``first character\*(''
313 of the terminal name used as
314 the intermediate level of a directory tree in (two-character) hexadecimal form.
316 As an example, here is a description for the Lear-Siegler
317 ADM\-3, a popular though rather stupid early terminal:
322 bel=^G, clear=\032$<1>, cr=^M, cub1=^H, cud1=^J,
323 cuf1=^L, cup=\\E=%p1%{32}%+%c%p2%{32}%+%c, cuu1=^K,
327 and a hexadecimal dump of the compiled terminal description:
330 \s-20000 1a 01 10 00 02 00 03 00 82 00 31 00 61 64 6d 33 ........ ..1.adm3
331 0010 61 7c 6c 73 69 20 61 64 6d 33 61 00 00 01 50 00 a|lsi ad m3a...P.
332 0020 ff ff 18 00 ff ff 00 00 02 00 ff ff ff ff 04 00 ........ ........
333 0030 ff ff ff ff ff ff ff ff 0a 00 25 00 27 00 ff ff ........ ..%.'...
334 0040 29 00 ff ff ff ff 2b 00 ff ff 2d 00 ff ff ff ff ).....+. ..-.....
335 0050 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
336 0060 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
337 0070 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
338 0080 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
339 0090 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
340 00a0 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
341 00b0 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
342 00c0 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
343 00d0 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
344 00e0 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
345 00f0 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
346 0100 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
347 0110 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
348 0120 ff ff ff ff ff ff 2f 00 07 00 0d 00 1a 24 3c 31 ....../. .....$<1
349 0130 3e 00 1b 3d 25 70 31 25 7b 33 32 7d 25 2b 25 63 >..=%p1% {32}%+%c
350 0140 25 70 32 25 7b 33 32 7d 25 2b 25 63 00 0a 00 1e %p2%{32} %+%c....
351 0150 00 08 00 0c 00 0b 00 0a 00 ........ .\s+2
358 total compiled entries cannot exceed 4096 bytes in the legacy format.
360 total compiled entries cannot exceed 32768 bytes in the extended format.
362 the name field cannot exceed 128 bytes.
364 \*d/*/* compiled terminal capability data base
366 \fBcurses\fR(3X), \fBterminfo\fR(\*n).
370 extended terminfo format for ncurses 5.0
372 hashed database support for ncurses 5.6
374 extended number support for ncurses 6.1
378 documented legacy terminfo format, e.g., from pcurses.