Hi,
to fix a (small) problem for v.digit which gets stalled
when the terminal is smaller that 80x24, I want to add
a related test. Something like
TERM_COLUMNS = getenv("COLUMNS");
TERM_ROWS = getenv("ROWS");
Of course that's not working, $COLUMNS seems not to be
generally present.
Is there a way to got COLUMNS and ROWS (sorry for the naive question)?
Maybe 'stty' (is that portable)?
Thanks for a hint,
Markus
Markus Neteler wrote:
to fix a (small) problem for v.digit which gets stalled
when the terminal is smaller that 80x24, I want to add
a related test. Something likeTERM_COLUMNS = getenv("COLUMNS");
TERM_ROWS = getenv("ROWS");Of course that's not working, $COLUMNS seems not to be
generally present.Is there a way to got COLUMNS and ROWS (sorry for the naive question)?
This is handled by the curses library:
The integer variables LINES and COLS are defined in
<curses.h> and will be filled in by initscr with the size
of the screen. The constants TRUE and FALSE have the val
ues 1 and 0, respectively.
Of course, as with all curses functionality, it requires that the
terminfo (or termcap) entry has the correct data.
Maybe 'stty' (is that portable)?
gtty(), tcgetattr() and ioctl(TCGETA) are concerned with low-level
issues such as flow control, parity, echo etc.
The size can be usually be obtained using ioctl(TIOCGWINSZ) (although
this may not work for a real terminal which is connected to a serial
port, it should work for any "terminal" which is implemented by a
user-space program, e.g. xterm, sshd, in.telnetd etc).
Most modern versions of curses will do this automatically and,
assuming that it provides sensible values, override the values from
terminfo (or termcap).
Also, if the terminal size changes, the foreground process group will
receive SIGWINCH. This will typically result in the curses library
calling ioctl(TIOCGWINSZ) and updating LINES and COLS accordingly.
--
Glynn Clements <glynn.clements@virgin.net>