These low-level routines must be called by programs that have to deal
- directly with the terminfo database to handle certain terminal capabil-
- ities, such as programming function keys. For all other functionality,
- curses routines are more suitable and their use is recommended.
+ directly with the terminfo database to handle certain terminal
+ capabilities, such as programming function keys. For all other
+ functionality, curses routines are more suitable and their use is
+ recommended.
- None of these functions use (or are aware of) multibyte character
+ None of these functions use (or are aware of) multibyte character
strings such as UTF-8:
o capability names use the POSIX portable character set
- o capability string values have no associated encoding; they are
+ o capability string values have no associated encoding; they are
strings of 8-bit characters.
Initially, setupterm should be called. The high-level curses functions
- initscr and newterm call setupterm to initialize the low-level set of
+ initscr and newterm call setupterm to initialize the low-level set of
terminal-dependent variables [listed in terminfo(5)].
- Applications can use the terminal capabilities either directly (via
- header definitions), or by special functions. The header files curs-
- es.h and term.h should be included (in this order) to get the defini-
- tions for these strings, numbers, and flags.
+ Applications can use the terminal capabilities either directly (via
+ header definitions), or by special functions. The header files
+ curses.h and term.h should be included (in this order) to get the
+ definitions for these strings, numbers, and flags.
- The terminfo variables lines and columns are initialized by setupterm
+ The terminfo variables lines and columns are initialized by setupterm
as follows:
- o If use_env(FALSE) has been called, values for lines and columns
+ o If use_env(FALSE) has been called, values for lines and columns
specified in terminfo are used.
- o Otherwise, if the environment variables LINES and COLUMNS exist,
+ o Otherwise, if the environment variables LINES and COLUMNS exist,
their values are used. If these environment variables do not exist
- and the program is running in a window, the current window size is
- used. Otherwise, if the environment variables do not exist, the
+ and the program is running in a window, the current window size is
+ used. Otherwise, if the environment variables do not exist, the
values for lines and columns specified in the terminfo database are
used.
- Parameterized strings should be passed through tparm to instantiate
- them. All terminfo strings (including the output of tparm) should be
- printed with tputs or putp. Call reset_shell_mode to restore the tty
+ Parameterized strings should be passed through tparm to instantiate
+ them. All terminfo strings (including the output of tparm) should be
+ printed with tputs or putp. Call reset_shell_mode to restore the tty
modes before exiting [see curs_kernel(3x)].
Programs which use cursor addressing should
@@ -160,55 +161,55 @@
Programs which execute shell subprocesses should
- o call reset_shell_mode and output exit_ca_mode before the shell is
+ o call reset_shell_mode and output exit_ca_mode before the shell is
called and
- o output enter_ca_mode and call reset_prog_mode after returning from
+ o output enter_ca_mode and call reset_prog_mode after returning from
the shell.
- The setupterm routine reads in the terminfo database, initializing the
- terminfo structures, but does not set up the output virtualization
+ The setupterm routine reads in the terminfo database, initializing the
+ terminfo structures, but does not set up the output virtualization
structures used by curses. These are its parameters:
term is the terminal type, a character string. If term is null, the
environment variable TERM is used.
filedes
- is the file descriptor used for getting and setting terminal
+ is the file descriptor used for getting and setting terminal
I/O modes.
- Higher-level applications use newterm(3x) for initializing the
- terminal, passing an output stream rather than a descriptor.
- In curses, the two are the same because newterm calls se-
- tupterm, passing the file descriptor derived from its output
+ Higher-level applications use newterm(3x) for initializing the
+ terminal, passing an output stream rather than a descriptor.
+ In curses, the two are the same because newterm calls
+ setupterm, passing the file descriptor derived from its output
stream parameter.
errret
- points to an optional location where an error status can be re-
- turned to the caller. If errret is not null, then setupterm
- returns OK or ERR and stores a status value in the integer
- pointed to by errret. A return value of OK combined with sta-
- tus of 1 in errret is normal.
+ points to an optional location where an error status can be
+ returned to the caller. If errret is not null, then setupterm
+ returns OK or ERR and stores a status value in the integer
+ pointed to by errret. A return value of OK combined with
+ status of 1 in errret is normal.
If ERR is returned, examine errret:
- 1 means that the terminal is hardcopy, cannot be used for
+ 1 means that the terminal is hardcopy, cannot be used for
curses applications.
- setupterm determines if the entry is a hardcopy type by
+ setupterm determines if the entry is a hardcopy type by
checking the hc (hardcopy) capability.
- 0 means that the terminal could not be found, or that it is
- a generic type, having too little information for curses
+ 0 means that the terminal could not be found, or that it is
+ a generic type, having too little information for curses
applications to run.
- setupterm determines if the entry is a generic type by
+ setupterm determines if the entry is a generic type by
checking the gn (generic_type) capability.
-1 means that the terminfo database could not be found.
- If errret is null, setupterm prints an error message upon find-
- ing an error and exits. Thus, the simplest call is:
+ If errret is null, setupterm prints an error message upon
+ finding an error and exits. Thus, the simplest call is:
setupterm((char*)0,1,(int*)0);,
@@ -216,122 +217,122 @@
- The setupterm routine stores its information about the terminal in a
- TERMINAL structure pointed to by the global variable cur_term. If it
- detects an error, or decides that the terminal is unsuitable (hardcopy
- or generic), it discards this information, making it not available to
+ The setupterm routine stores its information about the terminal in a
+ TERMINAL structure pointed to by the global variable cur_term. If it
+ detects an error, or decides that the terminal is unsuitable (hardcopy
+ or generic), it discards this information, making it not available to
applications.
- If setupterm is called repeatedly for the same terminal type, it will
- reuse the information. It maintains only one copy of a given termi-
- nal's capabilities in memory. If it is called for different terminal
- types, setupterm allocates new storage for each set of terminal capa-
- bilities.
+ If setupterm is called repeatedly for the same terminal type, it will
+ reuse the information. It maintains only one copy of a given
+ terminal's capabilities in memory. If it is called for different
+ terminal types, setupterm allocates new storage for each set of
+ terminal capabilities.
- The set_curterm routine sets cur_term to nterm, and makes all of the
- terminfo boolean, numeric, and string variables use the values from
+ The set_curterm routine sets cur_term to nterm, and makes all of the
+ terminfo boolean, numeric, and string variables use the values from
nterm. It returns the old value of cur_term.
- The del_curterm routine frees the space pointed to by oterm and makes
- it available for further use. If oterm is the same as cur_term, refer-
- ences to any of the terminfo boolean, numeric, and string variables
- thereafter may refer to invalid memory locations until another se-
- tupterm has been called.
+ The del_curterm routine frees the space pointed to by oterm and makes
+ it available for further use. If oterm is the same as cur_term,
+ references to any of the terminfo boolean, numeric, and string
+ variables thereafter may refer to invalid memory locations until
+ another setupterm has been called.
- The restartterm routine is similar to setupterm and initscr, except
- that it is called after restoring memory to a previous state (for exam-
- ple, when reloading a game saved as a core image dump). restartterm
- assumes that the windows and the input and output options are the same
- as when memory was saved, but the terminal type and baud rate may be
- different. Accordingly, restartterm saves various tty state bits,
- calls setupterm, and then restores the bits.
+ The restartterm routine is similar to setupterm and initscr, except
+ that it is called after restoring memory to a previous state (for
+ example, when reloading a game saved as a core image dump).
+ restartterm assumes that the windows and the input and output options
+ are the same as when memory was saved, but the terminal type and baud
+ rate may be different. Accordingly, restartterm saves various tty
+ state bits, calls setupterm, and then restores the bits.
- The tparm routine instantiates the string str with parameters pi. A
- pointer is returned to the result of str with the parameters applied.
- Application developers should keep in mind these quirks of the inter-
- face:
+ The tparm routine instantiates the string str with parameters pi. A
+ pointer is returned to the result of str with the parameters applied.
+ Application developers should keep in mind these quirks of the
+ interface:
- o Although tparm's actual parameters may be integers or strings, the
+ o Although tparm's actual parameters may be integers or strings, the
prototype expects long (integer) values.
- o Aside from the set_attributes (sgr) capability, most terminal capa-
- bilities require no more than one or two parameters.
+ o Aside from the set_attributes (sgr) capability, most terminal
+ capabilities require no more than one or two parameters.
- o Padding information is ignored by tparm; it is interpreted by
+ o Padding information is ignored by tparm; it is interpreted by
tputs.
- o The capability string is null-terminated. Use "\200" where an
+ o The capability string is null-terminated. Use "\200" where an
ASCII NUL is needed in the output.
- tiparm is a newer form of tparm which uses <stdarg.h> rather than a
+ tiparm is a newer form of tparm which uses <stdarg.h> rather than a
fixed-parameter list. Its numeric parameters are integers (int) rather
than longs.
- Both tparm and tiparm assume that the application passes parameters
- consistent with the terminal description. Two extensions are provided
+ Both tparm and tiparm assume that the application passes parameters
+ consistent with the terminal description. Two extensions are provided
as alternatives to deal with untrusted data:
- otiparm_s is an extension which is a safer formatting function than
+ otiparm_s is an extension which is a safer formatting function than
tparm or tiparm, because it allows the developer to tell the curses
- library how many parameters to expect in the parameter list, and
+ library how many parameters to expect in the parameter list, and
which may be string parameters.
- The mask parameter has one bit set for each of the parameters (up
+ The mask parameter has one bit set for each of the parameters (up
to 9) which will be passed as char* rather than numbers.
- o The extension tiscan_s allows the application to inspect a format-
- ting capability to see what the curses library would assume.
+ o The extension tiscan_s allows the application to inspect a
+ formatting capability to see what the curses library would assume.
- The tputs routine applies padding information (i.e., by interpreting
- marker embedded in the terminfo capability such as "$<5>" as 5 mil-
- liseconds) to the string str and outputs it:
+ The tputs routine applies padding information (i.e., by interpreting
+ marker embedded in the terminfo capability such as "$<5>" as 5
+ milliseconds) to the string str and outputs it:
- o The str parameter must be a terminfo string variable or the return
+ o The str parameter must be a terminfo string variable or the return
value from tparm, tiparm, tgetstr, or tgoto.
- The tgetstr and tgoto functions are part of the termcap interface,
- which happens to share this function name with the terminfo inter-
- face.
+ The tgetstr and tgoto functions are part of the termcap interface,
+ which happens to share this function name with the terminfo
+ interface.
oaffcnt is the number of lines affected, or 1 if not applicable.
- oputc is a putchar-like routine to which the characters are passed,
+ oputc is a putchar-like routine to which the characters are passed,
one at a time.
- The putp routine calls tputs(str,1,putchar). The output of putp al-
- ways goes to stdout, rather than the filedes specified in setupterm.
+ The putp routine calls tputs(str,1,putchar). The output of putp
+ always goes to stdout, rather than the filedes specified in setupterm.
- The vidputs routine displays the string on the terminal in the video
+ The vidputs routine displays the string on the terminal in the video
attribute mode attrs, which is any combination of the attributes listed
- in curses(3x). The characters are passed to the putchar-like routine
+ in curses(3x). The characters are passed to the putchar-like routine
putc.
The vidattr routine is like the vidputs routine, except that it outputs
through putchar.
- The vid_attr and vid_puts routines correspond to vidattr and vidputs,
- respectively. They use a set of arguments for representing the video
+ The vid_attr and vid_puts routines correspond to vidattr and vidputs,
+ respectively. They use a set of arguments for representing the video
attributes plus color, i.e.,
oattrs of type attr_t for the attributes and
opair of type short for the color-pair number.
- The vid_attr and vid_puts routines are designed to use the attribute
+ The vid_attr and vid_puts routines are designed to use the attribute
constants with the WA_ prefix.
- X/Open Curses reserves the opts argument for future use, saying that
- applications must provide a null pointer for that argument. As an ex-
- tension, this implementation allows opts to be used as a pointer to
+ X/Open Curses reserves the opts argument for future use, saying that
+ applications must provide a null pointer for that argument. As an
+ extension, this implementation allows opts to be used as a pointer to
int, which overrides the pair (short) argument.
- The mvcur routine provides low-level cursor motion. It takes effect
- immediately (rather than at the next refresh). Unlike the other low-
- level output functions, which either write to the standard output or
+ The mvcur routine provides low-level cursor motion. It takes effect
+ immediately (rather than at the next refresh). Unlike the other low-
+ level output functions, which either write to the standard output or
pass an output function parameter, mvcur uses an output file descriptor
derived from the output stream parameter of newterm(3x).
@@ -341,9 +342,9 @@
- The tigetflag, tigetnum and tigetstr routines return the value of the
- capability corresponding to the terminfocapname passed to them, such
- as xenl. The capname for each capability is given in the table column
+ The tigetflag, tigetnum and tigetstr routines return the value of the
+ capability corresponding to the terminfocapname passed to them, such
+ as xenl. The capname for each capability is given in the table column
entitled capname code in the capabilities section of terminfo(5).
These routines return special values to denote errors.
@@ -386,33 +387,34 @@
Each successful call to setupterm allocates memory to hold the terminal
- description. As a side-effect, it sets cur_term to point to this memo-
- ry. If an application calls
+ description. As a side-effect, it sets cur_term to point to this
+ memory. If an application calls
del_curterm(cur_term);
the memory will be freed.
- The formatting functions tparm and tiparm extend the storage allocated
+ The formatting functions tparm and tiparm extend the storage allocated
by setupterm:
- o the "static" terminfo variables [a-z]. Before ncurses 6.3, those
- were shared by all screens. With ncurses 6.3, those are allocated
+ o the "static" terminfo variables [a-z]. Before ncurses 6.3, those
+ were shared by all screens. With ncurses 6.3, those are allocated
per screen. See terminfo(5) for details.
- o to improve performance, ncurses 6.3 caches the result of analyzing
- terminfo strings for their parameter types. That is stored as a
+ o to improve performance, ncurses 6.3 caches the result of analyzing
+ terminfo strings for their parameter types. That is stored as a
binary tree referenced from the TERMINAL structure.
The higher-level initscr and newterm functions use setupterm. Normally
- they do not free this memory, but it is possible to do that using the
+ they do not free this memory, but it is possible to do that using the
delscreen(3x) function.
- Routines that return an integer return ERR upon failure and OK (SVr4
- only specifies "an integer value other than ERR") upon successful com-
- pletion, unless otherwise noted in the preceding routine descriptions.
+ Routines that return an integer return ERR upon failure and OK (SVr4
+ only specifies "an integer value other than ERR") upon successful
+ completion, unless otherwise noted in the preceding routine
+ descriptions.
Routines that return pointers always return NULL on error.
@@ -429,13 +431,13 @@
setupterm
returns an error if it cannot allocate enough memory, or create
- the initial windows (stdscr, curscr, newscr). Other error con-
- ditions are documented above.
+ the initial windows (stdscr, curscr, newscr). Other error
+ conditions are documented above.
tparm
- returns a null if the capability would require unexpected pa-
- rameters, e.g., too many, too few, or incorrect types (strings
- where integers are expected, or vice versa).
+ returns a null if the capability would require unexpected
+ parameters, e.g., too many, too few, or incorrect types
+ (strings where integers are expected, or vice versa).
tputs
returns an error if the string parameter is null. It does not
@@ -444,8 +446,8 @@
- This implementation provides a few macros for compatibility with sys-
- tems before SVr4 (see HISTORY). Those include crmode, fixterm,
+ This implementation provides a few macros for compatibility with
+ systems before SVr4 (see HISTORY). Those include crmode, fixterm,
gettmode, nocrmode, resetterm, saveterm, and setterm.
In SVr4, those are found in <curses.h>, but except for setterm, are
@@ -455,9 +457,9 @@
setupterm(term,1,(int*)0)
- provides the same functionality as setterm(term), and is not recommend-
- ed for new programs. This implementation provides each of those sym-
- bols as macros for BSD compatibility,
+ provides the same functionality as setterm(term), and is not
+ recommended for new programs. This implementation provides each of
+ those symbols as macros for BSD compatibility,
@@ -467,10 +469,11 @@
FunctionDescription
------------------------------------------------------------
fixterm restore tty to "in curses" state
+
gettmode establish current tty modes
mvcur low level cursor motion
- putp utility function that uses tputs to send char-
- acters via putchar.
+ putp utility function that uses tputs to send
+ characters via putchar.
resetterm set tty modes to "out of curses" state
resetty reset tty flags to stored value
saveterm save current modes as "in curses" state
@@ -499,8 +502,8 @@
Early terminfo programs obtained capability values from the TERMINAL
structure initialized by setupterm.
- SVr3 extended terminfo by adding functions to retrieve capability val-
- ues (like the termcap interface), and reusing tgoto and tputs:
+ SVr3 extended terminfo by adding functions to retrieve capability
+ values (like the termcap interface), and reusing tgoto and tputs:
FunctionDescription
-------------------------------------------
@@ -522,13 +525,13 @@
setterm setupterm
SVr3 kept the mvcur, vidattr and vidputs functions, along with putp,
- tparm and tputs. The latter were needed to support padding, and han-
- dling functions such as vidattr (which used more than the two parame-
- ters supported by tgoto).
+ tparm and tputs. The latter were needed to support padding, and
+ handling functions such as vidattr (which used more than the two
+ parameters supported by tgoto).
- SVr3 introduced the functions for switching between terminal descrip-
- tions, e.g., set_curterm. Some of that was incremental improvements to
- the SVr2 library:
+ SVr3 introduced the functions for switching between terminal
+ descriptions, e.g., set_curterm. Some of that was incremental
+ improvements to the SVr2 library:
o The TERMINAL type definition was introduced in SVr3.01, for the
term structure provided in SVr2.
@@ -540,16 +543,16 @@
SVr4 added the vid_attr and vid_puts functions.
There are other low-level functions declared in the curses header files
- on Unix systems, but none were documented. The functions marked "obso-
- lete" remained in use by the Unix vi(1) editor.
+ on Unix systems, but none were documented. The functions marked
+ "obsolete" remained in use by the Unix vi(1) editor.
The functions marked as extensions were designed for ncurses(3x), and
- are not found in SVr4 curses, 4.4BSD curses, or any other previous ver-
- sion of curses.
+ are not found in SVr4 curses, 4.4BSD curses, or any other previous
+ version of curses.
Older versions of ncurses assumed that the file descriptor passed to
setupterm from initscr or newterm uses buffered I/O, and would write to
- the corresponding stream. In addition to the limitation that the ter-
- minal was left in block-buffered mode on exit (like System V curses),
- it was problematic because ncurses did not allow a reliable way to
- cleanup on receiving SIGTSTP.
+ the corresponding stream. In addition to the limitation that the
+ terminal was left in block-buffered mode on exit (like System V
+ curses), it was problematic because ncurses did not allow a reliable
+ way to cleanup on receiving SIGTSTP.
The current version (ncurses6) uses output buffers managed directly by
ncurses. Some of the low-level functions described in this manual page
- write to the standard output. They are not signal-safe. The high-lev-
- el functions in ncurses use alternate versions of these functions using
- the more reliable buffering scheme.
+ write to the standard output. They are not signal-safe. The high-
+ level functions in ncurses use alternate versions of these functions
+ using the more reliable buffering scheme.
- The X/Open Curses prototypes are based on the SVr4 curses header decla-
- rations, which were defined at the same time the C language was first
- standardized in the late 1980s.
+ The X/Open Curses prototypes are based on the SVr4 curses header
+ declarations, which were defined at the same time the C language was
+ first standardized in the late 1980s.
o X/Open Curses uses const less effectively than a later design
might, in some cases applying it needlessly to values are already
@@ -604,8 +607,8 @@
o X/Open Curses prototypes tparm with a fixed number of parameters,
rather than a variable argument list.
- This implementation uses a variable argument list, but can be con-
- figured to use the fixed-parameter list. Portable applications
+ This implementation uses a variable argument list, but can be
+ configured to use the fixed-parameter list. Portable applications
should provide 9 parameters after the format; zeroes are fine for
this purpose.
@@ -622,23 +625,23 @@
nine on each call is awkward.
Using long for the numeric parameter type is a workaround to make
- the parameter use the same amount of stack as a pointer. That ap-
- proach dates back to the mid-1980s, before C was standardized.
+ the parameter use the same amount of stack as a pointer. That
+ approach dates back to the mid-1980s, before C was standardized.
Since then, there is a standard (and pointers are not required to
fit in a long).
o Providing the right number of parameters for a variadic function
- such as tiparm can be a problem, in particular for string parame-
- ters. However, only a few terminfo capabilities use string parame-
- ters (e.g., the ones used for programmable function keys).
+ such as tiparm can be a problem, in particular for string
+ parameters. However, only a few terminfo capabilities use string
+ parameters (e.g., the ones used for programmable function keys).
The ncurses library checks usage of these capabilities, and returns
an error if the capability mishandles string parameters. But it
cannot check if a calling program provides strings in the right
places for the tparm calls.
- The tput(1) program checks its use of these capabilities with a ta-
- ble, so that it calls tparm correctly.
+ The tput(1) program checks its use of these capabilities with a
+ table, so that it calls tparm correctly.
@@ -670,26 +673,26 @@
and does no error-checking.
X/Open notes that after calling mvcur, the curses state may not match
- the actual terminal state, and that an application should touch and re-
- fresh the window before resuming normal curses calls. Both ncurses and
- System V Release 4 curses implement mvcur using the SCREEN data allo-
- cated in either initscr or newterm. So though it is documented as a
- terminfo function, mvcur is really a curses function which is not well
- specified.
-
- X/Open states that the old location must be given for mvcur. This im-
- plementation allows the caller to use -1's for the old ordinates. In
+ the actual terminal state, and that an application should touch and
+ refresh the window before resuming normal curses calls. Both ncurses
+ and System V Release 4 curses implement mvcur using the SCREEN data
+ allocated in either initscr or newterm. So though it is documented as
+ a terminfo function, mvcur is really a curses function which is not
+ well specified.
+
+ X/Open states that the old location must be given for mvcur. This
+ implementation allows the caller to use -1's for the old ordinates. In
that case, the old location is unknown.