Re: buffering of process output

[storm@cua.dk (Kim F. Storm)]

no-spam@cua.dk (Kim F. Storm) writes:

> Andreas Schwab <schwab@suse.de> writes:
>
>> storm@cua.dk (Kim F. Storm) writes:
>>
>> It doesn't.  It's because there is no call to XFlush during the read loop
>> in call-process.  See the comment in xterm.c:
>>
>> /* Remove calls to XFlush by defining XFlush to an empty replacement.
>>    Calls to XFlush should be unnecessary because the X output buffer
>>    is flushed automatically as needed by calls to XPending,
>>    XNextEvent, or XWindowEvent according to the XFlush man page.
>>    XTread_socket calls XPending.  Removing XFlush improves
>>    performance.  */
>>
>> Thus redisplay_preserve_echo_area does not call XFlush any more.
>>
>> Andreas.
>
> Thanks for the explanation.  I'll fix that.

An explicit flush doesn't fix the problem -- it may have some effect,
but output is still buffered (at least) two lines per update.

I still see cases where the display is not really updated at all
(as if redisplay doesn't see that the display need update).

I'll keep investigating.

-- 
Kim F. Storm <storm@cua.dk> http://www.cua.dk