Re: emacs freezes

["Jose A. Ortega Ruiz" <jao@gnu.org>]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

>> Process 4067 attached - interrupt to quit
>> futex(0x407d9860, FUTEX_WAIT, 2, NULL)  = -1 EINTR (Interrupted system call)
>> --- SIGIO (I/O possible) @ 0 (0) ---
>> sigreturn()                             = ? (mask now [SEGV])
>
>> so it seems some kind of problem with the 'futex' syscall. I'm using
>> linux 2.6.8 (with the futex kernel config flag enabled) on a debian
>
> Could you explain what is "futex" ?
>

i'm not an expert, but they're a new (as of 2.6 kernels) low level
syncronisation primitive that work in user space and is used to
construct higher level abstractions such as mutexes or semaphores. i
guess they're used internally in calls like select. from the man page,
an EINTR during the system call above is provoked by "signals or other
spurious wakeups"... not that i can make much sense of it :(

>
> Better focus on the 21.3.50 version (the only one that might get fixed
> since the other is already released).  Send a detailed bug report to
> emacs-pretest-bug@gnu.org (ideally via M-x report-emacs-bug).
>

that's the version i'm use regularly. bug report sent. thank you.

jao
-- 
"Beware of bugs in the above code; I have only proved it correct,
not tried it." -- Donald Knuth (in a memo to Peter van Emde Boas)