X-Git-Url: https://ncurses.scripts.mit.edu/?p=ncurses.git;a=blobdiff_plain;f=doc%2Fhtml%2Fman%2Fresizeterm.3x.html;h=ca51d4a3e9f92ad0ff3591b3e89d337df052f49b;hp=9ad4fe776d148840027a4649fbd0c220b29f1d41;hb=f344f8539c1543f8cd65a5bb142dbaf23b9421d2;hpb=46722468f47c2b77b3987729b4bcf2321cccfd01;ds=sidebyside diff --git a/doc/html/man/resizeterm.3x.html b/doc/html/man/resizeterm.3x.html index 9ad4fe77..ca51d4a3 100644 --- a/doc/html/man/resizeterm.3x.html +++ b/doc/html/man/resizeterm.3x.html @@ -1,7 +1,6 @@ - +
+ +- +resizeterm(3x) resizeterm(3x) --
+ + + +
is_term_resized, resize_term, resizeterm - change the curses terminal size --
+
#include <curses.h> bool is_term_resized(int lines, int columns); @@ -57,42 +59,48 @@ int resizeterm(int lines, int columns); --
+
This is an extension to the curses library. It provides callers with a hook into the ncurses data to resize win- dows, primarily for use by programs running in an X Window - terminal (e.g., xterm). The function resizeterm resizes - the standard and current windows to the specified dimen- - sions, and adjusts other bookkeeping data used by the - ncurses library that record the window dimensions. + terminal (e.g., xterm). + - Most of the work is done by the inner function +
+ The function resizeterm resizes the standard and current + windows to the specified dimensions, and adjusts other + bookkeeping data used by the ncurses library that record + the window dimensions such as the LINES and COLS vari- + ables. + + +
+ Most of the work is done by the inner function resize_term. The outer function resizeterm adds bookkeep- - ing for the SIGWINCH handler. When resizing the windows, - resize_term blank-fills the areas that are extended. The + ing for the SIGWINCH handler. When resizing the windows, + resize_term blank-fills the areas that are extended. The calling application should fill in these areas with appro- - priate data. The resize_term function attempts to resize - all windows. However, due to the calling convention of - pads, it is not possible to resize these without addi- + priate data. The resize_term function attempts to resize + all windows. However, due to the calling convention of + pads, it is not possible to resize these without addi- tional interaction with the application. - A support function is_term_resized is provided so that - applications can check if the resize_term function would - modify the window structures. It returns TRUE if the win- - dows would be modified, and FALSE otherwise. +
+ A support function is_term_resized is provided so that + applications can check if the resize_term function would + modify the window structures. It returns TRUE if the win- + dows would be modified, and FALSE otherwise. --
- Except as notes, these function return the integer ERR - upon failure and OK on success. They will fail if either + +
+ Except as noted, these functions return the integer ERR + upon failure and OK on success. They will fail if either of the dimensions are less than or equal to zero, or if an - error occurs while (re)allocating memory for the windows. + error occurs while (re)allocating memory for the windows. --
+
While these functions are intended to be used to support a signal handler (i.e., for SIGWINCH), care should be taken to avoid invoking them in a context where malloc or real- @@ -100,75 +108,75 @@ tions. If ncurses is configured to supply its own SIGWINCH han- - dler, the resizeterm function ungetch's a KEY_RESIZE which - will be read on the next call to getch. This is used to - alert an application that the screen size has changed, and - that it should repaint special features such as pads that - cannot be done automatically. - - --
- wresize(3x). - - --
- Thomas Dickey (from an equivalent function written in 1988 - for BSD curses). - - - - - - - - - - - - - - - - - - - - - - - - - - - - + dler, + o on receipt of a SIGWINCH, the handler sets a flag + o which is tested in wgetch(3x) and doupdate, + o in turn, calling the resizeterm function, + o which ungetch's a KEY_RESIZE which will be read on the + next call to wgetch. + The KEY_RESIZE alerts an application that the screen + size has changed, and that it should repaint special + features such as pads that cannot be done automati- + cally. + Calling resizeterm or resize_term directly from a sig- + nal handler is unsafe. This indirect method is used + to provide a safe way to resize the ncurses data + structures. + If the environment variables LINES or COLUMNS are set, + this overrides the library's use of the window size + obtained from the operating system. Thus, even if a SIG- + WINCH is received, no screen size change may be recorded. +
+ It is possible to resize the screen with SVr4 curses, by + o exiting curses with endwin(3x) and + o resuming using refresh(3x). + Doing that clears the screen and is visually distracting. + This extension of ncurses was introduced in mid-1995. It + was adopted in NetBSD curses (2001) and PDCurses (2003). +
+ curs_getch(3x), curs_variables(3x), wresize(3x). +
+ Thomas Dickey (from an equivalent function written in 1988 + for BSD curses). + resizeterm(3x)-