- STORAGELOCATION
- Compiled terminfo descriptions are placed under the direc-
- tory /usr/share/terminfo. Two configurations are sup-
- ported (when building the ncurses libraries):
+
+ Compiled terminfo descriptions are placed under the directory
+ /usr/local/ncurses/lib/terminfo. Two configurations are supported
+ (when building the ncurses libraries):
directorytree
- 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.
+ A two-level scheme is used to avoid a linear search of a huge UNIX
+ system directory: /usr/local/ncurses/lib/terminfo/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/local/ncurses/lib/terminfo/a/act4. Synonyms for the same
+ terminal are implemented by multiple links to the same compiled
+ file.
hasheddatabase
- 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 pri-
- mary name as a key, and records containing only
+ Using Berkeley database, two types of records are stored: the ter-
+ minfo 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 pointing 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.
+ If built to write hashed databases, ncurses can still read ter-
+ minfo 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 TER-
+ MINFO_DIRS environment variable by assuming a directory tree for
+ entries that correspond to an existing directory, and hashed data-
+ base otherwise.
- 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.
- STORAGEFORMAT
- 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 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 order-
+ ing 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, num-
- bers, strings, and string table.
+ The compiled file is created with the tic program, and read by the rou-
+ tine setupterm(3x). 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
+ 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);
@@ -110,78 +104,69 @@
(3) the number of bytes in the boolean section;
- (4) the number of short integers in the numbers sec-
- tion;
+ (4) the number of short integers in the numbers section;
- (5) the number of offsets (short integers) in the
- strings 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*second+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 hard-
- ware of the VAX and PDP-11 (that is, little-endian
- machines). Machines where this does not correspond to the
- hardware must read the integers as two bytes and compute
- the little-endian value.
-
- The terminal names section comes next. It contains the
- first line of the terminfo description, listing the vari-
- ous names for the terminal, separated by the `|' charac-
- ter. The section is terminated with an ASCII NUL charac-
- ter.
-
- The boolean flags have one byte for each flag. This byte
- is either 0 or 1 as the flag is present or absent. The
- capabilities are in the same order as the file <term.h>.
-
- Between the boolean section and the number section, a null
- byte will be inserted, if necessary, to ensure that the
- number section begins on an even byte (this is a relic of
- the PDP-11's word-addressed architecture, originally
- designed in to avoid IOT traps induced by addressing a
- word on an odd byte boundary). All short integers 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 repre-
- sentation. Padding information $<nn> and parameter infor-
- mation %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
- section. Each string is null terminated.
-
- EXTENDEDSTORAGEFORMAT
- 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 predefined set of
- boolean, number or string capabilities.
-
- The ncurses libraries and applications support extended
- terminfo binary format, allowing users to define capabili-
- ties which are loaded at runtime. This extension is made
- possible by using the fact that the other implementations
- 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.
+ 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, lit-
+ tle-endian machines). Machines where this does not correspond to the
+ hardware must read the integers as two bytes and compute the little-
+ endian value.
+
+ The terminal names section comes next. It contains the first line of
+ the terminfo description, listing the various names for the terminal,
+ separated by the "|" character. 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 capabilities are in the
+ same order as the file <term.h>.
+
+ Between the boolean section and the number section, a null byte will be
+ inserted, if necessary, to ensure that the number section begins on an
+ even byte (this is a relic of the PDP-11's word-addressed architecture,
+ originally designed in to avoid IOT traps induced by addressing a word
+ on an odd byte boundary). All short integers 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 begin-
+ ning 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 section. Each string is
+ null terminated.
+
+
+
+ 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
+ predefined set of boolean, number or string capabilities.
+
+ The ncurses libraries and applications support extended terminfo binary
+ format, allowing users to define capabilities which are loaded at run-
+ time. This extension is made possible by using the fact that the other
+ implementations 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):
@@ -193,116 +178,157 @@
(4) size of the extended string table in bytes.
- (5) last offset 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 capabilities 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.
- Using the counts and sizes, ncurses allocates arrays and
- reads data for the extended capabilties in the same order
- as the header information.
+ Applications which manipulate terminal data can use the definitions
+ described in term_variables(3x) which associate the long capability
+ names with members of a TERMTYPE structure.
- The extended string table contains values for string capa-
- bilities. 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.
+
+ On occasion, 16-bit signed integers are not large enough. With ncurses
+ 6.1, a new format is introduced by making a few changes to the legacy
+ format:
-
-
PORTABILITY
- Note that it is possible for setupterm to expect a differ-
- ent 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 unrecog-
- nized 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 terminfo after SVr1,
- and have added extension capabilities to the string table
- that (in the binary format) collide with System V and XSI
- Curses extensions. See terminfo(5) for detailed discus-
- sion of terminfo source compatibility issues.
+ o a different magic number (0542)
+ o changing the type for the number array from signed 16-bit integers
+ to signed 32-bit integers.
-
+ Note that it is possible for setupterm to expect a different set of
+ capabilities than are actually present in the file. Either the data-
+ base may have been updated since setupterm has been recompiled (result-
+ ing 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 bool-
+ ean, number, and string capabilities.
-
-
LIMITS
- Some limitations: total compiled entries cannot exceed
- 4096 bytes. The name field cannot exceed 128 bytes.
+ Despite the consistent use of little-endian for numbers and the other-
+ wise 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 terminfo after SVr1, and
+ have added extension capabilities to the string table that (in the
+ binary format) collide with System V and XSI Curses extensions. See
+ terminfo(5) for detailed discussion of terminfo source compatibility
+ issues.
+ Direct access to the TERMTYPE structure is provided for legacy applica-
+ tions. Portable applications should use the tigetflag and related
+ functions described in curs_terminfo(3x) for reading terminal capabili-
+ ties.
-
-
FILES
- /usr/share/terminfo/*/* compiled terminal capability data
- base
+
+ Some limitations:
+
+ o total compiled entries cannot exceed 4096 bytes in the legacy for-
+ mat.
+
+ o total compiled entries cannot exceed 32768 bytes in the extended
+ format.
+
+ o the name field cannot exceed 128 bytes.
+
+
+
Thomas E. Dickey
extended terminfo format for ncurses 5.0
hashed database support for ncurses 5.6
+ extended number support for ncurses 6.1
Eric S. Raymond
+ documented legacy terminfo format, e.g., from pdcurses.
- term(5)
+ term(5)