X-Git-Url: https://ncurses.scripts.mit.edu/?p=ncurses.git;a=blobdiff_plain;f=man%2Fcurs_util.3x;h=4d027dbade11aa8337dce634df4ab57bd684c285;hp=de19a308c85f6136915c2f211256873104870f4e;hb=21c8ffa0edf2e389f3f674f0c08009002c6f357d;hpb=a8987e73ec254703634802b4f7ee30d3a485524d diff --git a/man/curs_util.3x b/man/curs_util.3x index de19a308..4d027dba 100644 --- a/man/curs_util.3x +++ b/man/curs_util.3x @@ -1,5 +1,6 @@ +'\" t .\"*************************************************************************** -.\" Copyright (c) 1998-2003,2004 Free Software Foundation, Inc. * +.\" Copyright (c) 1998-2013,2015 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 * @@ -26,8 +27,17 @@ .\" authorization. * .\"*************************************************************************** .\" -.\" $Id: curs_util.3x,v 1.12 2004/01/31 17:24:53 tom Exp $ +.\" $Id: curs_util.3x,v 1.43 2015/06/06 23:36:27 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 +.. +.na +.hy 0 .SH NAME \fBdelay_output\fR, \fBfilter\fR, @@ -35,16 +45,20 @@ \fBgetwin\fR, \fBkey_name\fR, \fBkeyname\fR, +\fBnofilter\fR, \fBputwin\fR, \fBunctrl\fR, \fBuse_env\fR, -\fBwunctrl\fR - miscellaneous \fBcurses\fR utility routines +\fBuse_tioctl\fR, +\fBwunctrl\fR \- miscellaneous \fBcurses\fR utility routines +.ad +.hy .SH SYNOPSIS \fB#include \fR .sp \fBchar *unctrl(chtype c);\fR .br -\fBchar *wunctrl(cchar_t *c);\fR +\fBwchar_t *wunctrl(cchar_t *c);\fR .br \fBchar *keyname(int c);\fR .br @@ -52,8 +66,12 @@ .br \fBvoid filter(void);\fR .br +\fBvoid nofilter(void);\fR +.br \fBvoid use_env(bool f);\fR .br +\fBvoid use_tioctl(bool f);\fR +.br \fBint putwin(WINDOW *win, FILE *filep);\fR .br \fBWINDOW *getwin(FILE *filep);\fR @@ -63,49 +81,165 @@ \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. +a wide character. +.SS keyname/key_name .PP -The \fBkeyname\fR routine returns a character string corresponding to the key \fIc\fR. +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. +.bP Control characters are displayed in the \fB^\fR\fIX\fR notation. -Values above 128 are either meta characters, shown in the \fBM-\fR\fIX\fR notation, -or the names of function keys, or null. +.bP +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 \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; +this follows the X/Open specification. +.bP +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. +.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 +\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. .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). -.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 \fBnofilter\fP routine cancels the effect of a preceding \fBfilter\fP +call. +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 ncurses 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 +If \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), +ncurses 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 +Ncurses also updates the screen size in response to SIGWINCH, +unless overridden by the \fBLINES\fR or \fBCOLUMNS\fR environment variables, +.SS use_tioctl +.PP +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, +ncurses 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, ncurses updates the corresponding environment variable +with the value that it has obtained via operating system call +or from the terminal database. +.bP +ncurses 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. +ncurses uses operating system calls +unless overridden by $LINES or $COLUMNS environment variables. +T} +TRUE/TRUE/T{ +ncurses updates $LINES and $COLUMNS based on operating system calls. +T} +FALSE/TRUE/T{ +ncurses ignores $LINES and $COLUMNS, uses operating system calls to obtain size. +T} +FALSE/FALSE/T{ +ncurses 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 (ncursesw) and +non-wide (ncurses) 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. @@ -114,33 +248,128 @@ Except for \fBflushinp\fR, routines that return an integer return \fBERR\fR upon failure and \fBOK\fR (SVr4 specifies only "an integer value other than \fBERR\fR") upon successful completion. .PP -\fBflushinp\fR always returns \fBOK\fR. -.PP Routines that return pointers return \fBNULL\fR on error. +.PP +X/Open does not define any error conditions. +In this implementation +.RS 3 +.TP 5 +\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 -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. +.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 +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 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 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. +.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 ncurses 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: +.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, +\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. +.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. +.bP +parameter values outside the 0 to 255 range. +\fBunctrl\fP returns a null pointer. .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 `^'. -Other implementations typically show both sets of control characters with `^', -and may strip the parameter to 7 bits. +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 \fBuse_legacy_coding\fP function allows the caller to +change the output of \fBunctrl\fP. +.PP +Likewise, the \fBmeta\fP 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. +X/Open Curses does not document the treatment of codes 128 to 159. +When treating them as \*(``meta\*('' keys +(or if \fBkeyname\fP is called before initializing curses), +this implementation returns strings \*(``M\-^@\*('', \*(``M\-^A\*('', etc. .SH SEE ALSO +\fBlegacy_coding\fR(3X), \fBcurses\fR(3X), \fBcurs_initscr\fR(3X), \fBcurs_kernel\fR(3X), -\fBcurs_scr_dump\fR(3X). -.\"# -.\"# The following sets edit modes for GNU EMACS -.\"# Local Variables: -.\"# mode:nroff -.\"# fill-column:79 -.\"# End: +\fBcurs_scr_dump\fR(3X), +\fBcurs_variables\fR(3X), +\fBlegacy_coding\fR(3X).