• Ian Lance Taylor's avatar
    runtime: for kqueue treat EVFILT_READ with EV_EOF as permitting a write · 23aad448
    Ian Lance Taylor authored
    On systems that use kqueue, we always register descriptors for both
    EVFILT_READ and EVFILT_WRITE. On at least FreeBSD and OpenBSD, when
    the write end of a pipe is registered for EVFILT_READ and EVFILT_WRITE
    events, and the read end of the pipe is closed, kqueue reports an
    EVFILT_READ event with EV_EOF set, but does not report an EVFILT_WRITE
    event. Since the write to the pipe is waiting for an EVFILT_WRITE
    event, closing the read end of a pipe can cause the write end to hang
    rather than attempt another write which will fail with EPIPE.
    
    Fix this by treating EVFILT_READ with EV_EOF set as making both reads
    and writes ready to proceed.
    
    The real test for this is in CL 71770, which tests using various
    timeouts with pipes.
    
    Updates #22114
    
    Change-Id: Ib23fbaaddbccd8eee77bdf18f27a7f0aa50e2742
    Reviewed-on: https://go-review.googlesource.com/71973Reviewed-by: 's avatarMatthew Dempsky <mdempsky@google.com>
    23aad448
defs_freebsd.go 3.36 KB