These low-level routines must be called by programs that
have to deal directly with the terminfo database to handle
certain terminal capabilities, such as programming func-
tion keys. For all other functionality, curses routines
are more suitable and their use is recommended.
- Initialization
- Initially, setupterm should be called. Note that se-
- tupterm is automatically called by initscr and newterm.
- This defines the set of terminal-dependent variables
- [listed in terminfo(5)].
- Each initialization routine provides applications with the
- terminal capabilities either directly (via header defini-
- tions), or by special functions. The header files curs-
- es.h and term.h should be included (in this order) to get
- the definitions for these strings, numbers, and flags.
+
+ Initially, setupterm should be called. The high-level
+ curses functions initscr and newterm call setupterm to
+ initialize the low-level set of terminal-dependent vari-
+ ables [listed in terminfo(5)].
+
+ Applications can use the terminal capabilities either di-
+ rectly (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 as follows:
@@ -138,102 +153,133 @@
The setupterm routine reads in the terminfo database, ini-
tializing the terminfo structures, but does not set up the
- output virtualization structures used by curses. The ter-
- minal type is the character string term; if term is null,
- the environment variable TERM is used. All output is to
- file descriptor fildes which is initialized for output.
- If errret is not null, then setupterm returns OK or ERR
- and stores a status value in the integer pointed to by er-
- rret. A return value of OK combined with status of 1 in
- errret is normal. If ERR is returned, examine errret:
+ 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 all output.
+
+ errret
+ points to an optional location where an error sta-
+ tus 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.
- 1 means that the terminal is hardcopy, cannot be used
- for curses applications.
+ If ERR is returned, examine errret:
- setupterm determines if the entry is a hardcopy type
- by checking the hc (hardcopy) capability.
+ 1 means that the terminal is hardcopy, cannot
+ be used for curses applications.
- 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 hard-
+ copy type by checking the hc (hardcopy) capa-
+ bility.
- setupterm determines if the entry is a generic type
- by checking the gn (generic) capability.
+ 0 means that the terminal could not be found,
+ or that it is a generic type, having too lit-
+ tle information for curses applications to
+ run.
- -1 means that the terminfo database could not be found.
+ setupterm determines if the entry is a gener-
+ ic type by checking the gn (generic) capabil-
+ ity.
- If errret is null, setupterm prints an error message upon
- finding an error and exits. Thus, the simplest call is:
+ -1 means that the terminfo database could not be
+ found.
- setupterm((char*)0,1,(int*)0);,
+ If errret is null, setupterm prints an error mes-
+ sage upon finding an error and exits. Thus, the
+ simplest call is:
- which uses all the defaults and sends the output to std-
- out.
+ setupterm((char*)0,1,(int*)0);,
+
+ which uses all the defaults and sends the output
+ to stdout.
The setterm routine was replaced by setupterm. The call:
setupterm(term,1,(int*)0)
- provides the same functionality as setterm(term). The
- setterm routine is provided for BSD compatibility, and is
+ provides the same functionality as setterm(term). The
+ setterm routine is provided for BSD compatibility, and is
not recommended for new programs.
- TheTerminalState
- 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 ap-
+
+
+ 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 ap-
plications.
- If setupterm is called repeatedly for the same terminal
- type, it will reuse the information. It maintains only
+ 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 allo-
cates new storage for each set of terminal capabilities.
- The set_curterm routine sets cur_term to nterm, and makes
+ 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
+ use the values from nterm. It returns the old value of
cur_term.
- The del_curterm routine frees the space pointed to by
+ 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 re-
- fer to invalid memory locations until another setupterm
+ the same as cur_term, references to any of the terminfo
+ boolean, numeric, and string variables thereafter may re-
+ fer 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 example, when reloading a game
+ 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
+ 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
+ may be different. Accordingly, restartterm saves various
+ tty state bits, calls setupterm, and then restores the
bits.
- FormattingOutput
+
+
The tparm routine instantiates the string str with parame-
- ters pi. A pointer is returned to the result of str with
- the parameters applied.
+ ters 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 prototype expects long (integer) values.
- tiparm is a newer form of tparm which uses <stdarg.h>
- rather than a fixed-parameter list. Its numeric parame-
+ o Aside from the set_attributes (sgr) capability, most
+ terminal capabilities require no more than one or two
+ parameters.
+
+ tiparm is a newer form of tparm which uses <stdarg.h>
+ rather than a fixed-parameter list. Its numeric parame-
ters are integers (int) rather than longs.
- OutputFunctions
- The tputs routine applies padding information to the
- string str and outputs it. The str must be a terminfo
- string variable or the return value from tparm, tgetstr,
- or tgoto. affcnt is the number of lines affected, or 1 if
- not applicable. putc is a putchar-like routine to which
- the characters are passed, one at a time.
- The putp routine calls tputs(str,1,putchar). Note that
- the output of putp always goes to stdout, not to the
- fildes specified in setupterm.
+
+ The tputs routine applies padding information to the
+ string str and outputs it:
+
+ o The str must be a terminfo string variable or the re-
+ turn value from tparm, tgetstr, or tgoto.
+
+ oaffcnt is the number of lines affected, or 1 if not
+ applicable.
+
+ 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 always goes to stdout, rather than the filedes
+ specified in setupterm.
The vidputs routine displays the string on the terminal in
the video attribute mode attrs, which is any combination
@@ -245,23 +291,31 @@
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.,
- one of type attr_t for the attributes and one of short for
- the color_pair number. The vid_attr and vid_puts routines
- are designed to use the attribute constants with the WA_
- prefix. The opts argument is reserved for future use.
- Currently, applications must provide a null pointer for
- that argument.
-
- The mvcur routine provides low-level cursor motion. It
- takes effect immediately (rather than at the next re-
+ 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 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 extension, this implementation al-
+ lows 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 re-
fresh).
- TerminalCapabilityFunctions
- The tigetflag, tigetnum and tigetstr routines return the
+
+
+ The tigetflag, tigetnum and tigetstr routines return the
value of the capability corresponding to the terminfocap-
- name passed to them, such as xenl. The capname for each
- capability is given in the table column entitled capname
+ name 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.
@@ -270,14 +324,14 @@
-1 if capname is not a boolean capability, or
- 0 if it is canceled or absent from the terminal de-
+ 0 if it is canceled or absent from the terminal de-
scription.
The tigetnum routine returns
-2 if capname is not a numeric capability, or
- -1 if it is canceled or absent from the terminal de-
+ -1 if it is canceled or absent from the terminal de-
scription.
The tigetstr routine returns
@@ -285,91 +339,146 @@
(char*)-1
if capname is not a string capability, or
- 0 if it is canceled or absent from the terminal de-
+ 0 if it is canceled or absent from the terminal de-
scription.
- TerminalCapabilityNames
- These null-terminated arrays contain the short terminfo
- names ("codes"), the termcap names, and the long terminfo
- names ("fnames") for each of the predefined terminfo vari-
- ables:
- char*boolnames[], *boolcodes[], *boolfnames[]
- char*numnames[], *numcodes[], *numfnames[]
+
+ These null-terminated arrays contain
- char*strnames[], *strcodes[], *strfnames[]
+ o the short terminfo names ("codes"),
+ o the termcap names ("names", and
-
-
RETURN VALUE
- 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
+ o the long terminfo names ("fnames")
+
+ for each of the predefined terminfo variables:
+
+ constchar*boolnames[], *boolcodes[], *boolf-
+ names[]
+ constchar*numnames[], *numcodes[], *numfnames[]
+ constchar*strnames[], *strcodes[], *strfnames[]
+
+
+
+ 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.
- X/Open defines no error conditions. In this implementa-
+ X/Open defines no error conditions. In this implementa-
tion
- del_curterm
- returns an error if its terminal parameter is
- null.
+ del_curterm
+ returns an error if its terminal parameter is
+ null.
- putp calls tputs, returning the same error-codes.
+ putp calls tputs, returning the same error-codes.
- restartterm
- returns an error if the associated call to se-
- tupterm returns an error.
+ restartterm
+ returns an error if the associated call to se-
+ tupterm returns an error.
- setupterm
- returns an error if it cannot allocate enough
- memory, or create the initial windows (stdscr,
- curscr, newscr). Other error conditions are
- documented above.
+ setupterm
+ returns an error if it cannot allocate enough mem-
+ ory, or create the initial windows (stdscr,
+ curscr, newscr). Other error conditions are docu-
+ mented above.
- tputs
- returns an error if the string parameter is
- null. It does not detect I/O errors: X/Open
- states that tputs ignores the return value of
- the output function putc.
+ tputs
+ returns an error if the string parameter is null.
+ It does not detect I/O errors: X/Open states that
+ tputs ignores the return value of the output func-
+ tion putc.
-
X/Open notes that vidattr and vidputs may be macros.
- The function setterm is not described by X/Open and must
- be considered non-portable. All other functions are as
+ The function setterm is not described by X/Open and must
+ be considered non-portable. All other functions are as
described by X/Open.
- setupterm copies the terminal name to the array ttytype.
- This is not part of X/Open Curses, but is assumed by some
+
+
+ setupterm copies the terminal name to the array ttytype.
+ This is not part of X/Open Curses, but is assumed by some
applications.
- If configured to use the terminal-driver, e.g., for the
- MinGW port,
+ Other implementions may not declare the capability name
+ arrays. Some provide them without declaring them. X/Open
+ does not specify them.
- osetupterm interprets a missing/empty TERM variable as
- the special value "unknown".
+ Extended terminal capability names, e.g., as defined by
+ tic-x, are not stored in the arrays described here.
- osetupterm allows explicit use of the the windows con-
- sole driver by checking if $TERM is set to "#win32con"
- or an abbreviation of that string.
+
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 ad-
dition to the limitation that the terminal was left in
- block-buffered mode on exit (like SystemV curses), it was
+ 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 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-
- level functions in ncurses use alternate versions of these
- functions using the more reliable buffering scheme.
+ to cleanup on receiving SIGTSTP.
+
+ The current version (ncurses6) uses output buffers managed
+ directly by ncurses. Some of the low-level functions de-
+ scribed in this manual page 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 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 constant, and in most cases over-
+ looking parameters which normally would use const.
+ Using constant parameters for functions which do not
+ use const may prevent the program from compiling. On
+ the other hand, writablestrings are an obsolescent
+ feature.
+
+ As an extension, this implementation can be configured
+ to change the function prototypes to use the const
+ keyword. The ncurses ABI 6 enables this feature by
+ default.
+
+ 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 configured to use the fixed-parameter list.
+ Portable applications should provide 9 parameters af-
+ ter the format; zeroes are fine for this purpose.
+
+ In response to review comments by Thomas E. Dickey,
+ X/Open Curses Issue 7 proposed the tiparm function in
+ mid-2009.
+
+
+
+ If configured to use the terminal-driver, e.g., for the
+ MinGW port,
+
+ osetupterm interprets a missing/empty TERM variable as
+ the special value "unknown".
+
+ osetupterm allows explicit use of the the windows con-
+ sole driver by checking if $TERM is set to "#win32con"
+ or an abbreviation of that string.
+
+
In System V Release 4, set_curterm has an int return type
and returns OK or ERR. We have chosen to implement the
X/Open Curses semantics.
@@ -381,16 +490,6 @@
turns a value other than OK/ERR from tputs. That returns
the length of the string, and does no error-checking.
- X/Open Curses prototypes tparm with a fixed number of pa-
- rameters, rather than a variable argument list. This im-
- plementation uses a variable argument list, but can be
- configured to use the fixed-parameter list. Portable ap-
- plications should provide 9 parameters after the format;
- zeroes are fine for this purpose.
-
- In response to comments by Thomas E. Dickey, X/Open Curses
- Issue 7 proposed the tiparm function in mid-2009.
-
X/Open notes that after calling mvcur, the curses state
may not match the actual terminal state, and that an ap-
plication should touch and refresh the window before re-
@@ -405,28 +504,43 @@
for the old ordinates. In that case, the old location is
unknown.
- Other implementions may not declare the capability name
- arrays. Some provide them without declaring them. X/Open
- does not specify them.
- Extended terminal capability names, e.g., as defined by
- tic-x, are not stored in the arrays described here.
-
-
-