Messages in this thread | | | Date | Wed, 4 May 2005 09:22:09 -0400 (EDT) | From | "Richard B. Johnson" <> | Subject | System call v.s. errno |
| |
Does anybody know for sure if global 'errno' is supposed to be altered after a successful system call? I'm trying to track down a problem where system calls return with EINTR even though all signal handlers are set with SA_RESTART in the flags. It appears as though there may be a race somewhere because if I directly set errno to 0x1234, within a few hundred system calls, it gets set to EINTR even though all system calls seemed to return 'good'. This makes it hard to trace down the real problem.
The answer is not obvious because the 'C' runtime library doesn't really give access to 'errno' instead it is dereferenced off some pointer returned from a function called __errno_location().
This problem does not exist with Linux-2.4.x. It started to show up when user's updated their machines to newer RH stuff that uses linux-2.6.5-1.358.
Cheers, Dick Johnson Penguin : Linux version 2.6.11 on an i686 machine (5537.79 BogoMips). Notice : All mail here is now cached for review by Dictator Bush. 98.36% of all statistics are fiction. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |