Re: EINTR from open() with smart scheduler

On Wed, 8 Jun 2005, William Waghorn wrote:

> I've recently been trying to track down a problem where calls to
> XCreateFontSet unexpectedly fail.  It turns out that while the X server
> process tries to open one of the requested fonts, there's a chance that
> the open call will fail with the error code EINTR when the new 'Smart
> Scheduler' is enabled.

> It is my understanding that code which uses timers must be prepared to
> retry any system call which can return an EINTR error.

> The new Smart Scheduler uses setitimer to configure a SIGALRM signal
> every 20ms.  Unfortunately, looking through the source (4.5.0) it would
> seem few if any calls to open() are retried after an EINTR error.  I
> guess there may be other calls which need to be retried too.

Actually, that's already done in a few cases.  For examples, `grep` the 
contents of hw/xfree86/os-support for "SYSCALL".  A patch for something 
similar in Xserver/os and Xserver/dix would probably be accepted.

Marc.

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