Re: File descriptor suddenly goes bad

From: Dan Mills (dmills_at_spamblock.demon.co.uk)
Date: 10/02/04

  • Next message: James Antill: "Re: Descriptor passed w/SCM_RIGHTS is invalid" 
    Date: Sat, 02 Oct 2004 21:12:18 +0100

    Kasper Dupont wrote:

    > Dan Mills wrote:
    >>
    >> Just a guess but do you fork and does the child then either exit or close
    >> the fd. There are IIRC some subtle issues involved here.
    >
    > That shouldn't cause any trouble. A shutdown call
    > on the socket might explain the problem.

    I had thought that there was some requirement to use _exit() in the child?

    <Reaches for APUE>

    If you open a file descriptor then fork the child inherits the open FD.
    Now closing it in one process is not a problem but some other socket
    operations may be.

    Does exit() shutdown any open sockets? How about _exit() which does less....

    Note that returning from main implies exit().

    Just guessing here. 

    -- 
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  • Next message: James Antill: "Re: Descriptor passed w/SCM_RIGHTS is invalid"

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