X-Git-Url: https://ncurses.scripts.mit.edu/?p=ncurses.git;a=blobdiff_plain;f=man%2Fcurs_util.3x;h=f833803a412dca6c3df227646d1acbf130438af1;hp=6781de7b3cfab0e781e920e1703978c0d7197982;hb=152c5a605234b7ea36ba3a03ec07e124bb6aac75;hpb=cef50b3afcd58166f3541b701c97bce538844c76 diff --git a/man/curs_util.3x b/man/curs_util.3x index 6781de7b..f833803a 100644 --- a/man/curs_util.3x +++ b/man/curs_util.3x @@ -1,5 +1,7 @@ +'\" t .\"*************************************************************************** -.\" Copyright (c) 1998-2008,2010 Free Software Foundation, Inc. * +.\" Copyright 2018-2019,2020 Thomas E. Dickey * +.\" Copyright 1998-2015,2017 Free Software Foundation, Inc. * .\" * .\" Permission is hereby granted, free of charge, to any person obtaining a * .\" copy of this software and associated documentation files (the * @@ -26,10 +28,15 @@ .\" authorization. * .\"*************************************************************************** .\" -.\" $Id: curs_util.3x,v 1.31 2010/10/02 23:21:45 tom Exp $ +.\" $Id: curs_util.3x,v 1.60 2020/12/19 22:44:46 tom Exp $ .TH curs_util 3X "" +.ie \n(.g .ds `` \(lq +.el .ds `` `` +.ie \n(.g .ds '' \(rq +.el .ds '' '' .de bP -.IP \(bu 4 +.ie n .IP \(bu 4 +.el .IP \(bu 2 .. .na .hy 0 @@ -44,46 +51,53 @@ \fBputwin\fR, \fBunctrl\fR, \fBuse_env\fR, +\fBuse_tioctl\fR, \fBwunctrl\fR \- miscellaneous \fBcurses\fR utility routines .ad .hy .SH SYNOPSIS \fB#include \fR .sp -\fBchar *unctrl(chtype c);\fR +\fBconst char *unctrl(chtype \fP\fIc\fP\fB);\fR .br -\fBwchar_t *wunctrl(cchar_t *c);\fR -.br -\fBchar *keyname(int c);\fR -.br -\fBchar *key_name(wchar_t w);\fR +\fBwchar_t *wunctrl(cchar_t *\fP\fIc\fP\fB);\fR +.sp +\fBconst char *keyname(int \fP\fIc\fP\fB);\fR .br +\fBconst char *key_name(wchar_t \fP\fIw\fP\fB);\fR +.sp \fBvoid filter(void);\fR .br \fBvoid nofilter(void);\fR +.sp +\fBvoid use_env(bool \fP\fIf\fP\fB);\fR .br -\fBvoid use_env(bool f);\fR -.br -\fBint putwin(WINDOW *win, FILE *filep);\fR -.br -\fBWINDOW *getwin(FILE *filep);\fR +\fBvoid use_tioctl(bool \fP\fIf\fP\fB);\fR +.sp +\fBint putwin(WINDOW *\fP\fIwin\fP\fB, FILE *\fP\fIfilep\fP\fB);\fR .br -\fBint delay_output(int ms);\fR +\fBWINDOW *getwin(FILE *\fP\fIfilep\fP\fB);\fR +.sp +\fBint delay_output(int \fP\fIms\fP\fB);\fR .br \fBint flushinp(void);\fR .br .SH DESCRIPTION +.SS unctrl +.PP The \fBunctrl\fR routine returns a character string which is a printable representation of the character \fIc\fR, ignoring attributes. Control characters are displayed in the \fB^\fR\fIX\fR notation. Printing characters are displayed as is. The corresponding \fBwunctrl\fR returns a printable representation of a wide character. +.SS keyname/key_name .PP -The \fBkeyname\fR routine returns a character string corresponding to the key \fIc\fR: -.RS 3 +The \fBkeyname\fR routine returns a character string +corresponding to the key \fIc\fR: .bP -Printable characters are displayed as themselves, e.g., a one-character string containing the key. +Printable characters are displayed as themselves, +e.g., a one-character string containing the key. .bP Control characters are displayed in the \fB^\fR\fIX\fR notation. .bP @@ -91,7 +105,7 @@ DEL (character 127) is displayed as \fB^?\fP. .bP Values above 128 are either meta characters (if the screen has not been initialized, -or if \fBmeta\fP has been called with a TRUE parameter), +or if \fBmeta\fP(3X) has been called with a \fBTRUE\fP parameter), shown in the \fBM\-\fR\fIX\fR notation, or are displayed as themselves. In the latter case, the values may not be printable; @@ -101,20 +115,34 @@ Values above 256 may be the names of the names of function keys. .bP Otherwise (if there is no corresponding name) the function returns null, to denote an error. -X/Open also lists an "UNKNOWN KEY" return value, which some implementations -return rather than null. -.RE +X/Open also lists an \*(``UNKNOWN KEY\*('' return value, +which some implementations return rather than null. .LP The corresponding \fBkey_name\fR returns a character string corresponding to the wide-character value \fIw\fR. The two functions do not return the same set of strings; the latter returns null where the former would display a meta character. +.SS filter/nofilter .PP The \fBfilter\fR routine, if used, must be called before \fBinitscr\fR or -\fBnewterm\fR are called. The effect is that, during those calls, \fBLINES\fR -is set to 1; the capabilities \fBclear\fR, \fBcup\fR, \fBcud\fR, \fBcud1\fR, -\fBcuu1\fR, \fBcuu\fR, \fBvpa\fR are disabled; and the \fBhome\fR string is -set to the value of \fBcr\fR. +\fBnewterm\fR are called. +Calling \fBfilter\fP causes these changes in initialization: +.bP +\fBLINES\fR is set to 1; +.bP +the capabilities +\fBclear\fR, +\fBcud1\fR, +\fBcud\fR, +\fBcup\fR, +\fBcuu1\fR, +\fBcuu\fR, +\fBvpa\fR +are disabled; +.bP +the capability \fBed\fP is disabled if \fBbce\fP is set; +.bP +and the \fBhome\fR string is set to the value of \fBcr\fR. .PP The \fBnofilter\fP routine cancels the effect of a preceding \fBfilter\fP call. @@ -122,30 +150,113 @@ That allows the caller to initialize a screen on a different device, using a different value of \fB$TERM\fP. The limitation arises because the \fBfilter\fP routine modifies the in-memory copy of the terminal information. +.SS use_env +.PP +The \fBuse_env\fR routine, if used, +should be called before \fBinitscr\fR or +\fBnewterm\fR are called +(because those compute the screen size). +It modifies the way \fBncurses\fP treats environment variables +when determining the screen size. +.bP +Normally \fBncurses\fP looks first at the terminal database for the screen size. +.IP +If \fBuse_env\fP was called with \fBFALSE\fP for parameter, +it stops here unless +\fBuse_tioctl\fP was also called with \fBTRUE\fP for parameter. +.bP +Then it asks for the screen size via operating system calls. +If successful, +it overrides the values from the terminal database. +.bP +Finally (unless \fBuse_env\fP was called with \fBFALSE\fP parameter), +\fBncurses\fP examines the \fBLINES\fR or \fBCOLUMNS\fR environment variables, +using a value in those to override the results +from the operating system or terminal database. +.IP +\fBNcurses\fP also updates the screen size in response to \fBSIGWINCH\fP, +unless overridden by the \fBLINES\fR or \fBCOLUMNS\fR environment variables, +.SS use_tioctl .PP -The \fBuse_env\fR routine, if used, is called before \fBinitscr\fR or -\fBnewterm\fR are called. When called with \fBFALSE\fR as an -argument, the values of \fBlines\fR and \fBcolumns\fR specified in the -\fIterminfo\fR database will be used, even if environment variables -\fBLINES\fR and \fBCOLUMNS\fR (used by default) are set, or if -\fBcurses\fR is running in a window (in which case default behavior -would be to use the window size if \fBLINES\fR and \fBCOLUMNS\fR are -not set). -Note that setting \fBLINES\fR or \fBCOLUMNS\fR overrides the -corresponding size which may be obtained from the operating system. -.PP -The \fBputwin\fR routine writes all data associated with window \fIwin\fR into -the file to which \fIfilep\fR points. This information can be later retrieved +The \fBuse_tioctl\fR routine, if used, +should be called before \fBinitscr\fR or \fBnewterm\fR are called +(because those compute the screen size). +After \fBuse_tioctl\fR is called with \fBTRUE\fR as an argument, +\fBncurses\fP modifies the last step in its computation +of screen size as follows: +.bP +checks if the \fBLINES\fR and \fBCOLUMNS\fR environment variables +are set to a number greater than zero. +.bP +for each, \fBncurses\fP updates the corresponding environment variable +with the value that it has obtained via operating system call +or from the terminal database. +.bP +\fBncurses\fP re-fetches the value of the environment variables so that +it is still the environment variables which set the screen size. +.PP +The \fBuse_env\fP and \fBuse_tioctl\fP routines combine as +summarized here: +.TS +center tab(/); +l l l +_ _ _ +lw7 lw7 lw40. +\fIuse_env\fR/\fIuse_tioctl\fR/\fISummary\fR +TRUE/FALSE/T{ +This is the default behavior. +\fBncurses\fP uses operating system calls +unless overridden by $LINES or $COLUMNS environment variables. +T} +TRUE/TRUE/T{ +\fBncurses\fP updates $LINES and $COLUMNS based on operating system calls. +T} +FALSE/TRUE/T{ +\fBncurses\fP ignores $LINES and $COLUMNS, +uses operating system calls to obtain size. +T} +FALSE/FALSE/T{ +\fBncurses\fP relies on the terminal database to determine size. +T} +.TE +.SS putwin/getwin +.PP +The \fBputwin\fR routine writes all data associated +with window (or pad) \fIwin\fR into +the file to which \fIfilep\fR points. +This information can be later retrieved using the \fBgetwin\fR function. .PP The \fBgetwin\fR routine reads window related data stored in the file by -\fBputwin\fR. The routine then creates and initializes a new window using that -data. It returns a pointer to the new window. +\fBputwin\fR. +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: +.bP +the data written is a copy of the \fBWINDOW\fP structure, +and its associated character cells. +The format differs between the wide-character (\fBncursesw\fP) and +non-wide (\fBncurses\fP) libraries. +You can transfer data between the two, however. +.bP +the retrieved window is always created as a top-level window (or pad), +rather than a subwindow. +.bP +the window's character cells contain the color pair \fIvalue\fP, +but not the actual color \fInumbers\fP. +If cells in the retrieved window use color pairs which have not been +created in the application using \fBinit_pair\fP, +they will not be colored when the window is refreshed. +.SS delay_output .PP The \fBdelay_output\fR routine inserts an \fIms\fR millisecond pause -in output. This routine should not be used extensively because +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 \fBnapms\fR to perform the delay. +If no padding character is specified, +this uses \fBnapms\fR to perform the delay. +.SS flushinp .PP The \fBflushinp\fR routine throws away any typeahead that has been typed by the user and has not yet been read by the program. @@ -163,91 +274,134 @@ In this implementation \fBflushinp\fR returns an error if the terminal was not initialized. .TP 5 -\fBmeta\fR -returns an error if the terminal was not initialized. -.TP 5 \fBputwin\fP returns an error if the associated \fBfwrite\fP calls return an error. .RE .SH PORTABILITY +.SS filter +.PP +The SVr4 documentation describes the action of \fBfilter\fR only in the vaguest +terms. +The description here is adapted from the XSI Curses standard (which +erroneously fails to describe the disabling of \fBcuu\fR). +.SS keyname +.PP +The \fBkeyname\fP function may return the names of user-defined +string capabilities which are defined in the terminfo entry via the \fB\-x\fP +option of \fB@TIC@\fP. +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 \fBuse_extended_names\fP(3X) function controls whether this data is +loaded when the terminal description is read by the library. +.SS nofilter/use_tioctl +.PP +The \fBnofilter\fP and \fBuse_tioctl\fP routines are specific to \fBncurses\fP. +They were not supported on Version 7, BSD or System V implementations. +It is recommended that any code depending on \fBncurses\fP extensions +be conditioned using NCURSES_VERSION. +.SS putwin/getwin +.PP +The \fBputwin\fP and \fBgetwin\fP functions have several issues with +portability: +.bP +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. +.IP +Interestingly enough, according to the copyright dates in Solaris source, +the functions (along with \fBscr_init\fP, 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. +.bP +Most implementations simply dump the binary \fBWINDOW\fP structure to the file. +These include SVr4 curses, NetBSD and PDCurses, +as well as older \fBncurses\fP versions. +This implementation +(as well as the X/Open variant of Solaris curses, dated 1995) +uses textual dumps. +.IP +The implementations which use binary dumps use block-I/O +(the \fBfwrite\fP and \fBfread\fP 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. +.SS unctrl/wunctrl +.PP The XSI Curses standard, Issue 4 describes these functions. It states that \fBunctrl\fR and \fBwunctrl\fR will return a null pointer if unsuccessful, but does not define any error conditions. This implementation checks for three cases: -.RS 3 .bP the parameter is a 7-bit US\-ASCII code. This is the case that X/Open Curses documented. .bP the parameter is in the range 128\-159, i.e., a C1 control code. -If \fBuse_legacy_coding\fP has been called with a \fB2\fP parameter, +If \fBuse_legacy_coding\fP(3X) has been called with a \fB2\fP parameter, \fBunctrl\fP 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. +Otherwise, it returns \*(``~@\*('', \*(``~A\*('', etc., +analogous to \*(``^@\*('', \*(``^A\*('', C0 controls. .IP X/Open Curses does not document whether \fBunctrl\fP can be called before initializing curses. This implementation permits that, -and returns the ``~@'', etc., values in that case. +and returns the \*(``~@\*('', etc., values in that case. .bP parameter values outside the 0 to 255 range. \fBunctrl\fP returns a null pointer. -.RE -.PP -The SVr4 documentation describes the action of \fBfilter\fR only in the vaguest -terms. The description here is adapted from the XSI Curses standard (which -erroneously fails to describe the disabling of \fBcuu\fR). .PP The strings returned by \fBunctrl\fR in this implementation are determined at compile time, -showing C1 controls from the upper-128 codes with a `~' prefix rather than `^'. +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 `^', +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 \fBuse_legacy_coding\fP function allows the caller to +The \fBuse_legacy_coding\fP(3X) function allows the caller to change the output of \fBunctrl\fP. .PP -Likewise, the \fBmeta\fP function allows the caller to change the +Likewise, the \fBmeta\fP(3X) function allows the caller to change the output of \fBkeyname\fP, i.e., -it determines whether to use the `M\-' prefix -for ``meta'' keys (codes in the range 128 to 255). -Both \fBuse_legacy_coding\fP and \fBmeta\fP succeed only after -curses is initialized. +it determines whether to use the \*(``M\-\*('' prefix +for \*(``meta\*('' keys (codes in the range 128 to 255). +Both \fBuse_legacy_coding\fP(3X) and \fBmeta\fP(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 +When treating them as \*(``meta\*('' keys (or if \fBkeyname\fP is called before initializing curses), -this implementation returns strings ``M\-^@'', ``M\-^A'', etc. +this implementation returns strings \*(``M\-^@\*('', \*(``M\-^A\*('', etc. .PP -The \fBkeyname\fP function may return the names of user-defined -string capabilities which are defined in the terminfo entry via the \fB\-x\fP -option of \fBtic\fP. -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 \fBuse_extended_names\fP function controls whether this data is -loaded when the terminal description is read by the library. +X/Open Curses documents \fBunctrl\fP as declared in \fB\fP, +which \fBncurses\fP does. +However, \fBncurses\fP' \fB\fP includes \fB\fP, +matching the behavior of SVr4 curses. +Other implementations may not do that. +.SS use_env/use_tioctl .PP -The \fBnofilter\fP 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 extensions -be conditioned using NCURSES_VERSION. +If \fBncurses\fP is configured to provide the sp-functions extension, +the state of \fBuse_env\fP and \fBuse_tioctl\fP may be updated before +creating each \fIscreen\fP rather than once only +(\fBcurs_sp_funcs\fR(3X)). +This feature of \fBuse_env\fP +is not provided by other implementation of curses. .SH SEE ALSO -\fBlegacy_coding\fR(3X), \fBcurses\fR(3X), \fBcurs_initscr\fR(3X), +\fBcurs_inopts\fR(3X), \fBcurs_kernel\fR(3X), \fBcurs_scr_dump\fR(3X), +\fBcurs_sp_funcs\fR(3X), \fBcurs_variables\fR(3X), \fBlegacy_coding\fR(3X). -.\"# -.\"# The following sets edit modes for GNU EMACS -.\"# Local Variables: -.\"# mode:nroff -.\"# fill-column:79 -.\"# End: