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diff --git a/upstream/opensuse-leap-15-6/man3/initscr.3ncurses b/upstream/opensuse-leap-15-6/man3/initscr.3ncurses new file mode 100644 index 00000000..5d8515f9 --- /dev/null +++ b/upstream/opensuse-leap-15-6/man3/initscr.3ncurses @@ -0,0 +1,255 @@ +.\"*************************************************************************** +.\" Copyright (c) 1998-2016,2017 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 * +.\" "Software"), to deal in the Software without restriction, including * +.\" without limitation the rights to use, copy, modify, merge, publish, * +.\" distribute, distribute with modifications, sublicense, and/or sell * +.\" copies of the Software, and to permit persons to whom the Software is * +.\" furnished to do so, subject to the following conditions: * +.\" * +.\" The above copyright notice and this permission notice shall be included * +.\" in all copies or substantial portions of the Software. * +.\" * +.\" THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * +.\" OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * +.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. * +.\" IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, * +.\" DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR * +.\" OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR * +.\" THE USE OR OTHER DEALINGS IN THE SOFTWARE. * +.\" * +.\" Except as contained in this notice, the name(s) of the above copyright * +.\" holders shall not be used in advertising or otherwise to promote the * +.\" sale, use or other dealings in this Software without prior written * +.\" authorization. * +.\"*************************************************************************** +.\" +.\" $Id: curs_initscr.3x,v 1.29 2017/11/18 23:47:37 tom Exp $ +.TH initscr 3NCURSES "" +.de bP +.ie n .IP \(bu 4 +.el .IP \(bu 2 +.. +.ie \n(.g .ds `` \(lq +.el .ds `` `` +.ie \n(.g .ds '' \(rq +.el .ds '' '' +.na +.hy 0 +.SH NAME +\fBinitscr\fR, +\fBnewterm\fR, +\fBendwin\fR, +\fBisendwin\fR, +\fBset_term\fR, +\fBdelscreen\fR \- \fBcurses\fR screen initialization and manipulation routines +.ad +.hy +.SH SYNOPSIS +\fB#include <ncursesw/curses.h>\fR +.sp +\fBWINDOW *initscr(void);\fR +.br +\fBint endwin(void);\fR +.br +\fBbool isendwin(void);\fR +.br +\fBSCREEN *newterm(char *\fP\fItype\fP\fB, FILE *\fP\fIoutfd\fP\fB, FILE *\fP\fIinfd\fP\fB);\fR +.br +\fBSCREEN *set_term(SCREEN *\fP\fInew\fP\fB);\fR +.br +\fBvoid delscreen(SCREEN* \fP\fIsp\fP\fB);\fR +.br +.SH DESCRIPTION +.SS initscr +\fBinitscr\fR is normally the first \fBcurses\fR routine to call when +initializing a program. +A few special routines sometimes need to be called before it; +these are \fBslk_init\fR(3X), \fBfilter\fR, \fBripoffline\fR, +\fBuse_env\fR. +For multiple-terminal applications, +\fBnewterm\fR may be called before \fBinitscr\fR. +.PP +The initscr code determines the terminal type and initializes all \fBcurses\fR +data structures. +\fBinitscr\fR also causes the first call to \fBrefresh\fR(3X) to clear the screen. +If errors occur, \fBinitscr\fR writes an appropriate error +message to standard error and exits; +otherwise, a pointer is returned to \fBstdscr\fR. +.SS newterm +.PP +A program that outputs to more than one terminal should use the \fBnewterm\fR +routine for each terminal instead of \fBinitscr\fR. +A program that needs to inspect capabilities, +so it can continue to run in a line-oriented mode if the +terminal cannot support a screen-oriented program, would also use +\fBnewterm\fR. +The routine \fBnewterm\fR should be called once for each terminal. +It returns a variable of type \fBSCREEN *\fR which should be saved +as a reference to that terminal. +\fBnewterm\fP's arguments are +.bP +the \fItype\fR of the terminal to be used in place of \fB$TERM\fR, +.bP +a file pointer for output to the terminal, and +.bP +another file pointer for input from the terminal +.PP +If the \fItype\fR parameter is \fBNULL\fR, \fB$TERM\fR will be used. +.SS endwin +.PP +The program must also call +\fBendwin\fR for each terminal being used before exiting from \fBcurses\fR. +If \fBnewterm\fR is called more than once for the same terminal, the first +terminal referred to must be the last one for which \fBendwin\fR is called. +.PP +A program should always call \fBendwin\fR before exiting or escaping from +\fBcurses\fR mode temporarily. +This routine +.bP +resets colors to correspond with the default color pair 0, +.bP +moves the cursor to the lower left-hand corner of the screen, +.bP +clears the remainder of the line so that it uses the default colors, +.bP +sets the cursor to normal visibility (see \fBcurs_set\fP(3X)), +.bP +stops cursor-addressing mode using the \fIexit_ca_mode\fP terminal capability, +.bP +restores tty modes (see \fBreset_shell_mode\fP(3X)). +.PP +Calling \fBrefresh\fR(3X) or \fBdoupdate\fR(3X) after a +temporary escape causes the program to resume visual mode. +.SS isendwin +.PP +The \fBisendwin\fR routine returns \fBTRUE\fR if \fBendwin\fR has been +called without any subsequent calls to \fBwrefresh\fR, +and \fBFALSE\fR otherwise. +.SS set_term +.PP +The \fBset_term\fR routine is used to switch between different terminals. +The screen reference \fBnew\fR becomes the new current terminal. +The previous terminal is returned by the routine. +This is the only routine which manipulates \fBSCREEN\fR pointers; +all other routines affect only the current terminal. +.SS delscreen +.PP +The \fBdelscreen\fR routine frees storage associated with the +\fBSCREEN\fR data structure. +The \fBendwin\fR routine does not do +this, so \fBdelscreen\fR should be called after \fBendwin\fR if a +particular \fBSCREEN\fR is no longer needed. +.SH RETURN VALUE +\fBendwin\fR returns the integer \fBERR\fR upon failure and \fBOK\fR +upon successful completion. +.PP +Routines that return pointers always return \fBNULL\fR on error. +.PP +X/Open defines no error conditions. +In this implementation +.bP +\fBendwin\fP returns an error if the terminal was not initialized. +.bP +\fBnewterm\fP +returns an error if it cannot allocate the data structures for the screen, +or for the top-level windows within the screen, +i.e., +\fBcurscr\fP, \fBnewscr\fP, or \fBstdscr\fP. +.bP +\fBset_term\fP +returns no error. +.SH PORTABILITY +These functions were described in the XSI Curses standard, Issue 4. +As of 2015, the current document is X/Open Curses, Issue 7. +.SS Differences +X/Open specifies that portable applications must not +call \fBinitscr\fR more than once: +.bP +The portable way to use \fBinitscr\fP is once only, +using \fBrefresh\fP (see curs_refresh(3X)) to restore the screen after \fBendwin\fP. +.bP +This implementation allows using \fBinitscr\fP after \fBendwin\fP. +.PP +Old versions of curses, e.g., BSD 4.4, may have returned a null pointer +from \fBinitscr\fR when an error is detected, rather than exiting. +It is safe but redundant to check the return value of \fBinitscr\fR +in XSI Curses. +.SS Unset TERM Variable +.PP +If the TERM variable is missing or empty, \fBinitscr\fP uses the +value \*(``unknown\*('', +which normally corresponds to a terminal entry with the \fIgeneric\fP +(\fIgn\fP) capability. +Generic entries are detected by \fBsetupterm\fP (see curs_terminfo(3X)) and cannot be +used for full-screen operation. +Other implementations may handle a missing/empty TERM variable differently. +.SS Signal Handlers +.PP +Quoting from X/Open Curses, section 3.1.1: +.RS 5 +.PP +\fICurses implementations may provide for special handling of the \fBSIGINT\fP, +\fBSIGQUIT\fP and \fBSIGTSTP\fP signals +if their disposition is \fBSIG_DFL\fP at the time +\fBinitscr\fP is called \fP... +.PP +\fIAny special handling for these signals may remain in effect for the +life of the process or until the process changes the disposition of +the signal.\fP +.PP +\fINone of the Curses functions are required to be safe with respect to signals \fP... +.RE +.PP +This implementation establishes signal handlers during initialization, +e.g., \fBinitscr\fP or \fBnewterm\fP. +Applications which must handle these signals should set up the corresponding +handlers \fIafter\fP initializing the library: +.TP 5 +.B SIGINT +The handler \fIattempts\fP to cleanup the screen on exit. +Although it \fIusually\fP works as expected, there are limitations: +.RS 5 +.bP +Walking the \fBSCREEN\fP list is unsafe, since all list management +is done without any signal blocking. +.bP +On systems which have \fBREENTRANT\fP turned on, \fBset_term\fP uses +functions which could deadlock or misbehave in other ways. +.bP +\fBendwin\fP calls other functions, many of which use stdio or +other library functions which are clearly unsafe. +.RE +.TP 5 +.B SIGTERM +This uses the same handler as \fBSIGINT\fP, with the same limitations. +It is not mentioned in X/Open Curses, but is more suitable for this +purpose than \fBSIGQUIT\fP (which is used in debugging). +.TP 5 +.B SIGTSTP +This handles the \fIstop\fP signal, used in job control. +When resuming the process, this implementation discards pending +input with \fBflushinput\fP (see curs_util(3X)), and repaints the screen +assuming that it has been completely altered. +It also updates the saved terminal modes with \fBdef_shell_mode\fP (see curs_kernel(3X)). +.TP 5 +.B SIGWINCH +This handles the window-size changes which were ignored in +the standardization efforts. +The handler sets a (signal-safe) variable +which is later tested in \fBwgetch\fP (see curs_getch(3X)). +If \fBkeypad\fP has been enabled for the corresponding window, +\fBwgetch\fP returns the key symbol \fBKEY_RESIZE\fP. +At the same time, \fBwgetch\fP calls \fBresizeterm\fP to adjust the +standard screen \fBstdscr\fP, +and update other data such as \fBLINES\fP and \fBCOLS\fP. +.SH SEE ALSO +\fBncurses\fR(3NCURSES), +\fBkernel\fR(3NCURSES), +\fBrefresh\fR(3NCURSES), +\fBslk\fR(3NCURSES), +\fBterminfo\fR(3NCURSES), +\fButil\fR(3NCURSES), +\fBcurses_variables\fR(3NCURSES). |