Home |
Licence |
FAQ |
Docs |
Download |
Keys |
Links
Mirrors |
Updates |
Feedback |
Changes |
Wishlist |
Team
pterm currently runs a GTK timer function every 20ms (fifty times a
second). This timer function takes care of calling term_update() to
handle actual window updates, calling term_blink() to handle
blinking cursors etc, and checking whether the child process has
terminated.
It would be nice if pterm could avoid doing this unless it was
absolutely necessary. So, alternative ways of doing the same things:
- to detect stuff in the child process, I'd have to get
asynchronous notification of SIGCHLD. I suppose this means having
an intra-process pipe in the same way Unix plink does it, so that
pty.c's SIGCHLD handler writes a byte to the pipe and the GTK
main function calls a function in response.
- the reason term_update() is called in the timer function is so
that it won't happen more than 50 times per second, which means
that really fast-scrolling text doesn't slow down pterm the way
it does xterm. So it would be a step backwards to move to just
calling term_update() after every term_out(). I think a sensible
way to fix this might be:
* Introduce a wrapper function in pterm.c, whose job is to
arrange a call to term_update either now or later.
* The wrapper function will first check how long it's been since
the last term_update. If it's been more than 20ms, it will
call term_update. If not, it should _schedule_ a GTK timer
function which will call term_update at some point 20ms or
less in the future. That timer function will then disable
itself the first time it runs.
* Then we call the wrapper function after every term_out().
- Regular calls to the terminal code are actually necessary if
blinking text or blinking cursor are enabled, or if a visual bell
is currently active. So I could introduce a spare function in
terminal.c which allows the front end to ask the terminal `Do you
have any pending events for which I should call you back in
future?' The wrapper function described above could call this
after term_update, and schedule the timer function _anyway_ if it
says yes.
Patch (unreviewed): Pine.LNX.4.53mb.0304291625260.25393@ask.diku.dk
Audit trail for this semi-bug.