X-Git-Url: https://ncurses.scripts.mit.edu/?a=blobdiff_plain;ds=sidebyside;f=doc%2Fhtml%2Fman%2Fcurs_util.3x.html;h=a923c7654fc9ccbdbd50cb710f5ea6aa17e4418a;hb=75a9c36c205ebefe07580acd0b1053a2abbd44b9;hp=dfef903a36193f6b91ceb7032fcbc21b7dc34796;hpb=ce4803687b821efbc5fb2c5a5f06d69cd4dc2656;p=ncurses.git diff --git a/doc/html/man/curs_util.3x.html b/doc/html/man/curs_util.3x.html index dfef903a..a923c765 100644 --- a/doc/html/man/curs_util.3x.html +++ b/doc/html/man/curs_util.3x.html @@ -1,7 +1,8 @@ -
- --curs_util(3x) curs_util(3x) +curs_util(3x) Library calls curs_util(3x)
- delay_output, filter, flushinp, getwin, key_name, keyname, - nofilter, putwin, unctrl, use_env, use_tioctl, wunctrl - - miscellaneous curses utility routines + delay_output, filter, flushinp, getwin, key_name, keyname, nofilter, + putwin, unctrl, use_env, use_tioctl, wunctrl - miscellaneous curses + utility routines
#include <curses.h> - char *unctrl(chtype c); - wchar_t *wunctrl(cchar_t *c); - char *keyname(int c); - char *key_name(wchar_t w); + const char *unctrl(chtype c); + wchar_t *wunctrl(cchar_t *c); + + const char *keyname(int c); + const char *key_name(wchar_t w); + void filter(void); - void nofilter(void); - void use_env(bool f); - void use_tioctl(bool f); - int putwin(WINDOW *win, FILE *filep); - WINDOW *getwin(FILE *filep); - int delay_output(int ms); + + void use_env(bool f); + + int putwin(WINDOW *win, FILE *filep); + WINDOW *getwin(FILE *filep); + + int delay_output(int ms); int flushinp(void); + /* extensions */ + void nofilter(void); + void use_tioctl(bool f); +
- The unctrl routine returns a character string which is a - printable representation of the character c, ignoring at- - tributes. Control characters are displayed in the ^X no- - tation. Printing characters are displayed as is. The - corresponding wunctrl returns a printable representation - of a wide character. - + The unctrl routine returns a character string which is a printable + representation of the character c: -
- The keyname routine returns a character string correspond- - ing to the key c: - - o Printable characters are displayed as themselves, - e.g., a one-character string containing the key. + o Printable characters are displayed as themselves, e.g., a one- + character string containing the key. o Control characters are displayed in the ^X notation. + o Printing characters are displayed as is. + o DEL (character 127) is displayed as ^?. - o Values above 128 are either meta characters (if the - screen has not been initialized, or if meta(3x) has - been called with a TRUE parameter), shown in the M-X - notation, or are displayed as themselves. In the lat- - ter case, the values may not be printable; this fol- - lows the X/Open specification. + o Values above 128 are either meta characters (if the screen has not + been initialized, or if meta(3x) has been called with a TRUE + parameter), shown in the M-X notation, or are displayed as + themselves. In the latter case, the values may not be printable; + this follows the X/Open specification. + + The corresponding wunctrl returns a printable representation of a + complex character c. + + In both unctrl and wunctrl the attributes and color associated with the + character parameter are ignored. + + +
+ The keyname routine returns a character string corresponding to the key + c. Key codes are different from character codes. - o Values above 256 may be the names of the names of - function keys. + o Key codes below 256 are characters. They are displayed using + unctrl. - o Otherwise (if there is no corresponding name) the - function returns null, to denote an error. X/Open al- - so lists an "UNKNOWN KEY" return value, which some im- - plementations return rather than null. + o Values above 256 may be the codes for function keys. The function + key name is displayed. - The corresponding key_name returns a character string cor- - responding to the wide-character value w. The two func- - tions do not return the same set of strings; the latter - returns null where the former would display a meta charac- - ter. + o Otherwise (if there is no corresponding name and the key is not a + character) the function returns null, to denote an error. X/Open + also lists an "UNKNOWN KEY" return value, which some + implementations return rather than null. + The corresponding key_name returns a multibyte character string + corresponding to the wide-character value w. The two functions + (keyname and key_name) do not return the same set of strings: -
- The filter routine, if used, must be called before initscr - or newterm are called. The effect is that, during those - calls, LINES is set to 1; the capabilities clear, cup, - cud, cud1, cuu1, cuu, vpa are disabled; and the home - string is set to the value of cr. + o keyname returns null where key_name would display a meta character. - The nofilter routine cancels the effect of a preceding - filter call. That allows the caller to initialize a - screen on a different device, using a different value of - $TERM. The limitation arises because the filter routine - modifies the in-memory copy of the terminal information. + o key_name does not return the name of a function key. + + +
+ The filter routine, if used, must be called before initscr or newterm + are called. Calling filter causes these changes in initialization: + + o LINES is set to 1; + + o the capabilities clear, cud1, cud, cup, cuu1, cuu, vpa are + disabled; + + o the capability ed is disabled if bce is set; + + o and the home string is set to the value of cr. + + The nofilter routine cancels the effect of a preceding filter call. + That allows the caller to initialize a screen on a different device, + using a different value of $TERM. The limitation arises because the + filter routine modifies the in-memory copy of the terminal information.
- The use_env routine, if used, should be called before - initscr or newterm are called (because those compute the - screen size). It modifies the way ncurses treats environ- - ment variables when determining the screen size. + The use_env routine, if used, should be called before initscr or + newterm are called (because those compute the screen size). It + modifies the way ncurses treats environment variables when determining + the screen size. - o Normally ncurses looks first at the terminal database - for the screen size. + o Normally ncurses looks first at the terminal database for the + screen size. - If use_env was called with FALSE for parameter, it - stops here unless If use_tioctl was also called with - TRUE for parameter. + If use_env was called with FALSE for parameter, it stops here + unless use_tioctl was also called with TRUE for parameter. - o Then it asks for the screen size via operating system - calls. If successful, it overrides the values from - the terminal database. + o Then it asks for the screen size via operating system calls. If + successful, it overrides the values from the terminal database. - o Finally (unless use_env was called with FALSE parame- - ter), ncurses examines the LINES or COLUMNS environ- - ment variables, using a value in those to override the - results from the operating system or terminal data- - base. + o Finally (unless use_env was called with FALSE parameter), ncurses + examines the LINES or COLUMNS environment variables, using a value + in those to override the results from the operating system or + terminal database. - Ncurses also updates the screen size in response to - SIGWINCH, unless overridden by the LINES or COLUMNS - environment variables, + curses also updates the screen size in response to SIGWINCH, unless + overridden by the LINES or COLUMNS environment variables,
- The use_tioctl routine, if used, should be called before - initscr or newterm are called (because those compute the - screen size). After use_tioctl is called with TRUE as an - argument, ncurses modifies the last step in its computa- - tion of screen size as follows: + The use_tioctl routine, if used, should be called before initscr or + newterm are called (because those compute the screen size). After + use_tioctl is called with TRUE as an argument, ncurses modifies the + last step in its computation of screen size as follows: - o checks if the LINES and COLUMNS environment variables - are set to a number greater than zero. + o checks if the LINES and COLUMNS environment variables are set to a + number greater than zero. - o for each, ncurses updates the corresponding environ- - ment variable with the value that it has obtained via - operating system call or from the terminal database. + o for each, ncurses updates the corresponding environment variable + with the value that it has obtained via operating system call or + from the terminal database. - o ncurses re-fetches the value of the environment vari- - ables so that it is still the environment variables - which set the screen size. + o ncurses re-fetches the value of the environment variables so that + it is still the environment variables which set the screen size. - The use_env and use_tioctl routines combine as summarized - here: + The use_env and use_tioctl routines combine as follows. - use_env use_tioctl Summary - ---------------------------------------------------------------- + use_env use_tioctl Summary + ----------------------------------------------------------------- + TRUE FALSE This is the default behavior. ncurses + uses operating system calls unless + overridden by LINES or COLUMNS + environment variables; default. + TRUE TRUE ncurses updates LINES and COLUMNS based + on operating system calls. + FALSE TRUE ncurses ignores LINES and COLUMNS, using + operating system calls to obtain size. +
+ The putwin routine writes all data associated with window (or pad) win + into the file to which filep points. This information can be later + retrieved using the getwin function. - TRUE FALSE This is the default behavior. ncurses - uses operating system calls unless over- - ridden by $LINES or $COLUMNS environment - variables. - TRUE TRUE ncurses updates $LINES and $COLUMNS - based on operating system calls. - FALSE TRUE ncurses ignores $LINES and $COLUMNS, us- - es operating system calls to obtain - size. - FALSE FALSE ncurses relies on the terminal database - to determine size. + The getwin routine reads window related data stored in the file by + putwin. The routine then creates and initializes a new window using + that data. It returns a pointer to the new window. There are a few + caveats: + o the data written is a copy of the WINDOW structure, and its + associated character cells. The format differs between the wide- + character (ncursesw) and non-wide (ncurses) libraries. You can + transfer data between the two, however. -
- The putwin routine writes all data associated with window - (or pad) win into the file to which filep points. This - information can be later retrieved using the getwin func- - tion. + o the retrieved window is always created as a top-level window (or + pad), rather than a subwindow. - The getwin routine reads window related data stored in the - file by putwin. The routine then creates and initializes - a new window using that data. It returns a pointer to the - new window. There are a few caveats: + o the window's character cells contain the color pair value, but not + the actual color numbers. If cells in the retrieved window use + color pairs which have not been created in the application using + init_pair, they will not be colored when the window is refreshed. - o the data written is a copy of the WINDOW structure, - and its associated character cells. The format dif- - fers between the wide-character (ncursesw) and non- - wide (ncurses) libraries. You can transfer data be- - tween the two, however. - o the retrieved window is always created as a top-level - window (or pad), rather than a subwindow. +
+ The delay_output routine inserts an ms millisecond pause in output. + Employ this function judiciously when terminal output uses padding, + because ncurses transmits null characters (consuming CPU and I/O + resources) instead of sleeping and requesting resumption from the + operating system. Padding is used unless: - o the window's character cells contain the color pair - value, but not the actual color numbers. If cells in - the retrieved window use color pairs which have not - been created in the application using init_pair, they - will not be colored when the window is refreshed. + o the terminal description has npc (no_pad_char) capability, or + o the environment variable NCURSES_NO_PADDING is set. -
- The delay_output routine inserts an ms millisecond pause - in output. This routine should not be used extensively - because padding characters are used rather than a CPU - pause. If no padding character is specified, this uses - napms to perform the delay. + If padding is not in use, ncurses uses napms to perform the delay. If + the value of ms exceeds 30,000 (thirty seconds), it is capped at that + value.
- The flushinp routine throws away any typeahead that has - been typed by the user and has not yet been read by the - program. + The flushinp routine throws away any typeahead that has been typed by + the user and has not yet been read by the program.
- Except for flushinp, routines that return an integer re- - turn ERR upon failure and OK (SVr4 specifies only "an in- - teger value other than ERR") upon successful completion. + Except for flushinp, routines that return an integer return ERR upon + failure and OK (SVr4 specifies only "an integer value other than ERR") + upon successful completion. Routines that return pointers return NULL on error. - X/Open does not define any error conditions. In this im- - plementation + X/Open Curses does not specify any error conditions. In this + implementation flushinp - returns an error if the terminal was not initial- - ized. + returns an error if the terminal was not initialized. putwin - returns an error if the associated fwrite calls - return an error. + returns an error if the associated fwrite calls return an + error.
- The SVr4 documentation describes the action of filter only - in the vaguest terms. The description here is adapted - from the XSI Curses standard (which erroneously fails to - describe the disabling of cuu). + The SVr4 documentation describes the action of filter only in the + vaguest terms. The description here is adapted from the XSI Curses + standard (which erroneously fails to describe the disabling of cuu). + + +
+ The limitation to 30 seconds and the use of napms differ from other + implementations. + + o SVr4 curses does not delay if no padding character is available. + + o NetBSD curses uses napms when no padding character is available, + but does not take timing into account when using the padding + character. + + Neither limits the delay.
- The keyname function may return the names of user-defined - string capabilities which are defined in the terminfo en- - try via the -x option of tic. This implementation auto- - matically assigns at run-time keycodes to user-defined - strings which begin with "k". The keycodes start at - KEY_MAX, but are not guaranteed to be the same value for - different runs because user-defined codes are merged from - all terminal descriptions which have been loaded. The - use_extended_names function controls whether this data is - loaded when the terminal description is read by the li- - brary. - - -
- The nofilter and use_tioctl routines are specific to - ncurses. They were not supported on Version 7, BSD or - System V implementations. It is recommended that any code - depending on ncurses extensions be conditioned using - NCURSES_VERSION. - - -
- The putwin and getwin functions have several issues with - portability: - - o The files written and read by these functions use an - implementation-specific format. Although the format - is an obvious target for standardization, it has been - overlooked. - - Interestingly enough, according to the copyright dates - in Solaris source, the functions (along with scr_init, - etc.) originated with the University of California, - Berkeley (in 1982) and were later (in 1988) incorpo- - rated into SVr4. Oddly, there are no such functions + The keyname function may return the names of user-defined string + capabilities which are defined in the terminfo entry via the -x option + of tic. This implementation automatically assigns at run-time keycodes + to user-defined strings which begin with "k". The keycodes start at + KEY_MAX, but are not guaranteed to be the same value for different runs + because user-defined codes are merged from all terminal descriptions + which have been loaded. The use_extended_names(3x) function controls + whether this data is loaded when the terminal description is read by + the library. + + +
+ The nofilter and use_tioctl routines are specific to ncurses. They + were not supported on Version 7, BSD or System V implementations. It + is recommended that any code depending on ncurses extensions be + conditioned using NCURSES_VERSION. + + +
+ The putwin and getwin functions have several issues with portability: + + o The files written and read by these functions use an + implementation-specific format. Although the format is an obvious + target for standardization, it has been overlooked. + + Interestingly enough, according to the copyright dates in Solaris + source, the functions (along with scr_init, etc.) originated with + the University of California, Berkeley (in 1982) and were later (in + 1988) incorporated into SVr4. Oddly, there are no such functions in the 4.3BSD curses sources. - o Most implementations simply dump the binary WINDOW - structure to the file. These include SVr4 curses, - NetBSD and PDCurses, as well as older ncurses ver- - sions. This implementation (as well as the X/Open - variant of Solaris curses, dated 1995) uses textual - dumps. - - The implementations which use binary dumps use block- - I/O (the fwrite and fread functions). Those that use - textual dumps use buffered-I/O. A few applications - may happen to write extra data in the file using these - functions. Doing that can run into problems mixing - block- and buffered-I/O. This implementation reduces - the problem on writes by flushing the output. Howev- - er, reading from a file written using mixed schemes - may not be successful. - - -
- The XSI Curses standard, Issue 4 describes these func- - tions. It states that unctrl and wunctrl will return a - null pointer if unsuccessful, but does not define any er- - ror conditions. This implementation checks for three cas- - es: - - o the parameter is a 7-bit US-ASCII code. This is the - case that X/Open Curses documented. - - o the parameter is in the range 128-159, i.e., a C1 con- - trol code. If use_legacy_coding has been called with - a 2 parameter, unctrl returns the parameter, i.e., a - one-character string with the parameter as the first - character. Otherwise, it returns "~@", "~A", etc., - analogous to "^@", "^A", C0 controls. - - X/Open Curses does not document whether unctrl can be - called before initializing curses. This implementa- - tion permits that, and returns the "~@", etc., values - in that case. - - o parameter values outside the 0 to 255 range. unctrl - returns a null pointer. - - The strings returned by unctrl in this implementation are - determined at compile time, showing C1 controls from the - upper-128 codes with a "~" prefix rather than "^". Other - implementations have different conventions. For example, - they may show both sets of control characters with "^", - and strip the parameter to 7 bits. Or they may ignore C1 - controls and treat all of the upper-128 codes as print- - able. This implementation uses 8 bits but does not modify - the string to reflect locale. The use_legacy_coding func- - tion allows the caller to change the output of unctrl. - - Likewise, the meta(3x) function allows the caller to - change the output of keyname, i.e., it determines whether - to use the "M-" prefix for "meta" keys (codes in the range - 128 to 255). Both use_legacy_coding and meta succeed only - after curses is initialized. X/Open Curses does not docu- - ment the treatment of codes 128 to 159. When treating - them as "meta" keys (or if keyname is called before ini- - tializing curses), this implementation returns strings + o Most implementations simply dump the binary WINDOW structure to the + file. These include SVr4 curses, NetBSD and PDCurses, as well as + older ncurses versions. This implementation (as well as the X/Open + variant of Solaris curses, dated 1995) uses textual dumps. + + The implementations which use binary dumps use block-I/O (the + fwrite and fread functions). Those that use textual dumps use + buffered-I/O. A few applications may happen to write extra data in + the file using these functions. Doing that can run into problems + mixing block- and buffered-I/O. This implementation reduces the + problem on writes by flushing the output. However, reading from a + file written using mixed schemes may not be successful. + + +
+ The XSI Curses standard, Issue 4 describes these functions. It states + that unctrl and wunctrl will return a null pointer if unsuccessful, but + does not define any error conditions. This implementation checks for + three cases: + + o the parameter is a 7-bit US-ASCII code. This is the case that + X/Open Curses documented. + + o the parameter is in the range 128-159, i.e., a C1 control code. If + use_legacy_coding(3x) has been called with a 2 parameter, unctrl + returns the parameter, i.e., a one-character string with the + parameter as the first character. Otherwise, it returns "~@", + "~A", etc., analogous to "^@", "^A", C0 controls. + + X/Open Curses does not document whether unctrl can be called before + initializing curses. This implementation permits that, and returns + the "~@", etc., values in that case. + + o parameter values outside the 0 to 255 range. unctrl returns a null + pointer. + + The strings returned by unctrl in this implementation are determined at + compile time, showing C1 controls from the upper-128 codes with a "~" + prefix rather than "^". Other implementations have different + conventions. For example, they may show both sets of control + characters with "^", and strip the parameter to 7 bits. Or they may + ignore C1 controls and treat all of the upper-128 codes as printable. + This implementation uses 8 bits but does not modify the string to + reflect locale. The use_legacy_coding(3x) function allows the caller + to change the output of unctrl. + + Likewise, the meta(3x) function allows the caller to change the output + of keyname, i.e., it determines whether to use the "M-" prefix for + "meta" keys (codes in the range 128 to 255). Both + use_legacy_coding(3x) and meta(3x) succeed only after curses is + initialized. X/Open Curses does not document the treatment of codes + 128 to 159. When treating them as "meta" keys (or if keyname is called + before initializing curses), this implementation returns strings "M-^@", "M-^A", etc. + X/Open Curses documents unctrl as declared in <unctrl.h>, which ncurses + does. However, ncurses' <curses.h> includes <unctrl.h>, matching the + behavior of SVr4 curses. Other implementations may not do that. + -
- If ncurses is configured to provide the sp-functions ex- - tension, the state of use_env and use_tioctl may be updat- - ed before creating each screen rather than once only - (curs_sp_funcs(3x)). This feature of use_env is not pro- - vided by other implementation of curses. +
+ If ncurses is configured to provide the sp-functions extension, the + state of use_env and use_tioctl may be updated before creating each + screen rather than once only (curs_sp_funcs(3x)). This feature of + use_env is not provided by other implementations of curses.
- legacy_coding(3x), curses(3x), curs_initscr(3x), curs_in- - opts(3x), curs_kernel(3x), curs_scr_dump(3x), - curs_sp_funcs(3x), curs_variables(3x), legacy_coding(3x). + curses(3x), curs_initscr(3x), curs_inopts(3x), curs_kernel(3x), + curs_scr_dump(3x), curs_sp_funcs(3x), curs_variables(3x), + legacy_coding(3x) - curs_util(3x) +ncurses 6.4 2024-03-16 curs_util(3x)