X-Git-Url: https://ncurses.scripts.mit.edu/?a=blobdiff_plain;f=doc%2Fhtml%2Fman%2Fcurs_util.3x.html;h=09b376484e3703e6be924c8aecdefceb3a6490f0;hb=02c4e383be9337e73a0e75844dfd1047745adb28;hp=b377bcbee4a84371693e8312f6762facf650f28b;hpb=ca276baf720e3a44721b9e18955d3f546955c6c8;p=ncurses.git diff --git a/doc/html/man/curs_util.3x.html b/doc/html/man/curs_util.3x.html index b377bcbe..09b37648 100644 --- a/doc/html/man/curs_util.3x.html +++ b/doc/html/man/curs_util.3x.html @@ -1,7 +1,7 @@ - +
+ +- -curs_util(3x) curs_util(3x) +curs_util(3x) curs_util(3x) --
- delay_output, filter, flushinp, getwin, key_name, keyname, - nofilter, putwin, unctrl, use_env, 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); @@ -63,175 +62,321 @@ 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); int flushinp(void); --
- 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 keyname routine returns a character string correspond- - ing to the key c. Control characters are displayed in the - ^X notation. Values above 128 are either meta characters, - shown in the M-X notation, or the names of function keys, - or null. The corresponding key_name returns a character - string corresponding to the wide-character value w. The - two functions do not return the same set of strings; the - latter returns null where the former would display a meta - character. - - 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. - - 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, is called before initscr or - newterm are called. When called with FALSE as an argu- - ment, the values of lines and columns specified in the - terminfo database will be used, even if environment vari- - ables LINES and COLUMNS (used by default) are set, or if - curses is running in a window (in which case default be- - havior would be to use the window size if LINES and - COLUMNS are not set). Note that setting LINES or COLUMNS - overrides the corresponding size which may be obtained - from the operating system. - - The putwin routine writes all data associated with window - win into the file to which filep points. This information - can be later retrieved using the getwin function. - - 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. - - 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. - - The flushinp routine throws away any typeahead that has - been typed by the user and has not yet been read by the - program. +
+
+ The unctrl routine returns a character string which is a printable rep- + resentation of the character c, ignoring attributes. Control charac- + ters are displayed in the ^X notation. Printing characters are dis- + played as is. The corresponding wunctrl returns a printable represen- + tation of a wide character. --
- 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. + +
+ The keyname routine returns a character string corresponding to the key + c: + + o Printable characters are displayed as themselves, e.g., a one-char- + acter string containing the key. + + o Control characters are displayed in the ^X notation. + + 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 param- + eter), 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. + + o Values above 256 may be the names of the names of function keys. + + o Otherwise (if there is no corresponding name) the function returns + null, to denote an error. X/Open also lists an "UNKNOWN KEY" re- + turn value, which some implementations return rather than null. + + The corresponding key_name returns a character string corresponding to + the wide-character value w. The two functions do not return the same + set of strings; the latter returns null where the former would display + a meta character. + + +
+ 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 dis- + abled; + + 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 modi- + fies the way ncurses treats environment variables when determining 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 un- + less 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 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 ter- + minal database. + + Ncurses also updates the screen size in response to SIGWINCH, un- + less 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 computation of screen size as follows: + + o checks if the LINES and COLUMNS environment variables are set to a + number greater than zero. + + 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 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: + + use_env use_tioctl Summary + ---------------------------------------------------------------- + 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 putwin routine writes all data associated with window (or pad) win + into the file to which filep points. This information can be later re- + trieved using the getwin function. + + 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 associ- + ated character cells. The format differs between the wide-charac- + ter (ncursesw) and non-wide (ncurses) libraries. You can transfer + data between the two, however. + + o the retrieved window is always created as a top-level window (or + pad), rather than a subwindow. + + 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. + + +
+ 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 speci- + fied, this uses napms to perform the delay. + + +
+ 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 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 does not define any error conditions. In this implementation + + flushinp + returns an error if the terminal was not initialized. - flushinp - returns an error if the terminal was not ini- - tialized. + putwin + returns an error if the associated fwrite calls return an er- + ror. + + +
- putwin - 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 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: - - - the parameter is a 7-bit US-ASCII code. This - is the case that X/Open Curses documented. - - - the parameter is in the range 128-159, i.e., a - C1 control 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 implementation permits that, and returns - the ``~@'', etc., values in that case. - - - parameter values outside the 0 to 255 range. - unctrl returns a null pointer. - - 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 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 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 af- - ter 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 - ``M-^@'', ``M-^A'', etc. - - 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 nofilter routine is specific to ncurses. It was not - supported on Version 7, BSD or System V implementations. - It is recommended that any code depending on ncurses ex- - tensions be conditioned using NCURSES_VERSION. +
+ The keyname function may return the names of user-defined string capa- + bilities 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. --
- legacy_coding(3x), curses(3x), curs_initscr(3x), curs_ker- - nel(3x), curs_scr_dump(3x), legacy_coding(3x). +
+ 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 condi- + tioned using NCURSES_VERSION. + + +
+ The putwin and getwin functions have several issues with portability: + + o The files written and read by these functions use an implementa- + tion-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 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 has been called with a 2 parameter, unctrl re- + turns the parameter, i.e., a one-character string with the parame- + ter 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 conven- + tions. 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 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 + and meta 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. - curs_util(3x) +
+ 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 implementation of curses. + + +
+ legacy_coding(3x), curses(3x), curs_initscr(3x), curs_inopts(3x), + curs_kernel(3x), curs_scr_dump(3x), curs_sp_funcs(3x), curs_vari- + ables(3x), legacy_coding(3x). + + + + curs_util(3x)-