NAME¶
is_term_resized,
resize_term,
resizeterm - change the
curses terminal size
SYNOPSIS¶
#include <curses.h>
bool is_term_resized(int lines, int columns);
int resize_term(int lines, int columns);
int resizeterm(int lines, int columns);
DESCRIPTION¶
This is an extension to the curses library. It provides callers with a hook into
the
ncurses data to resize windows, 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 dimensions, and
adjusts other bookkeeping data used by the
ncurses library that record
the window dimensions such as the
LINES and
COLS variables.
Most of the work is done by the inner function
resize_term. The outer
function
resizeterm adds bookkeeping 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 appropriate
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 additional 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 windows would be modified, and FALSE otherwise.
RETURN VALUE¶
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.
NOTES¶
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
realloc may have been interrupted, since it uses those
functions.
If ncurses is configured to supply its own SIGWINCH handler, 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.
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 SIGWINCH is received, no screen size change may be
recorded.
SEE ALSO¶
getch(3NCURSES),
curses_variables(3NCURSES),
wresize(3NCURSES).
AUTHOR¶
Thomas Dickey (from an equivalent function written in 1988 for BSD
curses).