| blob | a4cca9c30964f3901bb948980439590a008c4f42 |
1 .\"***************************************************************************
2 .\" Copyright (c) 1998-2010,2015 Free Software Foundation, Inc. *
3 .\" *
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: *
11 .\" *
12 .\" The above copyright notice and this permission notice shall be included *
13 .\" in all copies or substantial portions of the Software. *
14 .\" *
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. *
22 .\" *
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 *
26 .\" authorization. *
27 .\"***************************************************************************
28 .\"
29 .\" $Id: term.5,v 1.22 2015/04/26 14:50:23 tom Exp $
30 .TH term 5
31 .ds n 5
32 .ds d @TERMINFO@
33 .SH NAME
34 term \- format of compiled term file.
35 .SH SYNOPSIS
36 .B term
37 .SH DESCRIPTION
38 .SS STORAGE LOCATION
39 Compiled terminfo descriptions are placed under the directory \fB\*d\fP.
40 Two configurations are supported (when building the ncurses libraries):
41 .TP 5
42 .B directory tree
43 A two-level scheme is used to avoid a linear search
44 of a huge \s-1UNIX\s+1 system directory: \fB\*d/c/name\fP where
45 .I name
46 is the name of the terminal, and
47 .I c
48 is the first character of
49 .IR name .
50 Thus,
51 .I act4
52 can be found in the file \fB\*d/a/act4\fP.
53 Synonyms for the same terminal are implemented by multiple
54 links to the same compiled file.
55 .TP 5
56 .B hashed database
57 Using Berkeley database, two types of records are stored:
58 the terminfo data in the same format as stored in a directory tree with
59 the terminfo's primary name as a key,
60 and records containing only aliases pointing to the primary name.
61 .IP
62 If built to write hashed databases,
63 ncurses can still read terminfo databases organized as a directory tree,
64 but cannot write entries into the directory tree.
65 It can write (or rewrite) entries in the hashed database.
66 .IP
67 ncurses distinguishes the two cases in the TERMINFO and TERMINFO_DIRS
68 environment variable by assuming a directory tree for entries that
69 correspond to an existing directory,
70 and hashed database otherwise.
71 .SS STORAGE FORMAT
72 The format has been chosen so that it will be the same on all hardware.
73 An 8 or more bit byte is assumed, but no assumptions about byte ordering
74 or sign extension are made.
75 .PP
76 The compiled file is created with the
77 .B @TIC@
78 program, and read by the routine
79 .IR setupterm .
80 The file is divided into six parts:
81 the header,
82 terminal names,
83 boolean flags,
84 numbers,
85 strings,
86 and
87 string table.
88 .PP
89 The header section begins the file.
90 This section contains six short integers in the format
91 described below.
92 These integers are
93 .RS 5
94 .TP 5
95 (1) the magic number (octal 0432);
96 .TP 5
97 (2) the size, in bytes, of the names section;
98 .TP 5
99 (3) the number of bytes in the boolean section;
100 .TP 5
101 (4) the number of short integers in the numbers section;
102 .TP 5
103 (5) the number of offsets (short integers) in the strings section;
104 .TP 5
105 (6) the size, in bytes, of the string table.
106 .RE
107 .PP
108 Short integers are stored in two 8-bit bytes.
109 The first byte contains the least significant 8 bits of the value,
110 and the second byte contains the most significant 8 bits.
111 (Thus, the value represented is 256*second+first.)
112 The value \-1 is represented by the two bytes 0377, 0377; other negative
113 values are illegal. This value generally
114 means that the corresponding capability is missing from this terminal.
115 Note that this format corresponds to the hardware of the \s-1VAX\s+1
116 and \s-1PDP\s+1-11 (that is, little-endian machines).
117 Machines where this does not correspond to the hardware must read the
118 integers as two bytes and compute the little-endian value.
119 .PP
120 The terminal names section comes next.
121 It contains the first line of the terminfo description,
122 listing the various names for the terminal,
123 separated by the `|' character.
124 The section is terminated with an \s-1ASCII NUL\s+1 character.
125 .PP
126 The boolean flags have one byte for each flag.
127 This byte is either 0 or 1 as the flag is present or absent.
128 The capabilities are in the same order as the file <term.h>.
129 .PP
130 Between the boolean section and the number section,
131 a null byte will be inserted, if necessary,
132 to ensure that the number section begins on an even byte (this is a
133 relic of the PDP\-11's word-addressed architecture, originally
134 designed in to avoid IOT traps induced by addressing a word on an
135 odd byte boundary).
136 All short integers are aligned on a short word boundary.
137 .PP
138 The numbers section is similar to the flags section.
139 Each capability takes up two bytes,
140 and is stored as a little-endian short integer.
141 If the value represented is \-1, the capability is taken to be missing.
142 .PP
143 The strings section is also similar.
144 Each capability is stored as a short integer, in the format above.
145 A value of \-1 means the capability is missing.
146 Otherwise, the value is taken as an offset from the beginning
147 of the string table.
148 Special characters in ^X or \ec notation are stored in their
149 interpreted form, not the printing representation.
150 Padding information $<nn> and parameter information %x are
151 stored intact in uninterpreted form.
152 .PP
153 The final section is the string table.
154 It contains all the values of string capabilities referenced in
155 the string section.
156 Each string is null terminated.
157 .SS EXTENDED STORAGE FORMAT
158 The previous section describes the conventional terminfo binary format.
159 With some minor variations of the offsets (see PORTABILITY),
160 the same binary format is used in all modern UNIX systems.
161 Each system uses a predefined set of boolean, number or string capabilities.
162 .PP
163 The ncurses libraries and applications support extended terminfo binary format,
164 allowing users to define capabilities which are loaded at runtime. This
165 extension is made possible by using the fact that the other implementations
166 stop reading the terminfo data when they have reached the end of the size given
167 in the header.
168 ncurses checks the size, and if it exceeds that due to the predefined data,
169 continues to parse according to its own scheme.
170 .PP
171 First, it reads the extended header (5 short integers):
172 .RS 5
173 .TP 5
174 (1)
175 count of extended boolean capabilities
176 .TP 5
177 (2)
178 count of extended numeric capabilities
179 .TP 5
180 (3)
181 count of extended string capabilities
182 .TP 5
183 (4)
184 size of the extended string table in bytes.
185 .TP 5
186 (5)
187 last offset of the extended string table in bytes.
188 .RE
189 .PP
190 Using the counts and sizes, ncurses allocates arrays and reads data
191 for the extended capabilities in the same order as the header information.
192 .PP
193 The extended string table contains values for string capabilities.
194 After the end of these values, it contains the names for each of
195 the extended capabilities in order, e.g., booleans, then numbers and
196 finally strings.
197 .
198 .SH PORTABILITY
199 Note that it is possible for
200 .I setupterm
201 to expect a different set of capabilities
202 than are actually present in the file.
203 Either the database may have been updated since
204 .I setupterm
205 has been recompiled
206 (resulting in extra unrecognized entries in the file)
207 or the program may have been recompiled more recently
208 than the database was updated
209 (resulting in missing entries).
210 The routine
211 .I setupterm
212 must be prepared for both possibilities \-
213 this is why the numbers and sizes are included.
214 Also, new capabilities must always be added at the end of the lists
215 of boolean, number, and string capabilities.
216 .PP
217 Despite the consistent use of little-endian for numbers and the otherwise
218 self-describing format, it is not wise to count on portability of binary
219 terminfo entries between commercial UNIX versions. The problem is that there
220 are at least three versions of terminfo (under HP\-UX, AIX, and OSF/1) which
221 diverged from System V terminfo after SVr1, and have added extension
222 capabilities to the string table that (in the binary format) collide with
223 System V and XSI Curses extensions. See \fBterminfo\fR(\*n) for detailed
224 discussion of terminfo source compatibility issues.
225 .SH EXAMPLE
226 As an example, here is a hex dump of the description for the Lear-Siegler
227 ADM\-3, a popular though rather stupid early terminal:
228 .nf
229 .sp
230 adm3a|lsi adm3a,
231 am,
232 cols#80, lines#24,
233 bel=^G, clear=\032$<1>, cr=^M, cub1=^H, cud1=^J,
234 cuf1=^L, cup=\\E=%p1%{32}%+%c%p2%{32}%+%c, cuu1=^K,
235 home=^^, ind=^J,
236 .sp
237 .ft CW
238 \s-20000 1a 01 10 00 02 00 03 00 82 00 31 00 61 64 6d 33 ........ ..1.adm3
239 0010 61 7c 6c 73 69 20 61 64 6d 33 61 00 00 01 50 00 a|lsi ad m3a...P.
240 0020 ff ff 18 00 ff ff 00 00 02 00 ff ff ff ff 04 00 ........ ........
241 0030 ff ff ff ff ff ff ff ff 0a 00 25 00 27 00 ff ff ........ ..%.'...
242 0040 29 00 ff ff ff ff 2b 00 ff ff 2d 00 ff ff ff ff ).....+. ..-.....
243 0050 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
244 0060 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
245 0070 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
246 0080 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
247 0090 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
248 00a0 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
249 00b0 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
250 00c0 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
251 00d0 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
252 00e0 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
253 00f0 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
254 0100 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
255 0110 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ........ ........
256 0120 ff ff ff ff ff ff 2f 00 07 00 0d 00 1a 24 3c 31 ....../. .....$<1
257 0130 3e 00 1b 3d 25 70 31 25 7b 33 32 7d 25 2b 25 63 >..=%p1% {32}%+%c
258 0140 25 70 32 25 7b 33 32 7d 25 2b 25 63 00 0a 00 1e %p2%{32} %+%c....
259 0150 00 08 00 0c 00 0b 00 0a 00 ........ .\s+2
260 .ft R
261 .fi
262 .sp
263 .SH LIMITS
264 Some limitations: total compiled entries cannot exceed 4096 bytes.
265 The name field cannot exceed 128 bytes.
266 .SH FILES
267 \*d/*/* compiled terminal capability data base
268 .SH SEE ALSO
269 \fBcurses\fR(3X), \fBterminfo\fR(\*n).
270 .SH AUTHORS
271 Thomas E. Dickey
272 .br
273 extended terminfo format for ncurses 5.0
274 .br
275 hashed database support for ncurses 5.6
276 .sp
277 Eric S. Raymond