On Wed, Feb 15, 2023 at 03:11:47PM +0100, Laszlo Ersek wrote:
 A comment currently states that "*the* socket must be set to
non-blocking
 only in the parent" (emphasis mine). This is a thinko: it implies that we
 have just one file descriptor, and that the underlying file description
 (which is manipulated by fcntl()'s F_GETFL and F_SETFL) is shared by the
 parent and the child processes. That's not the case: we have *two* sockets
 here (a socket pair), one of which is used by the parent exclusively, and
 the other is used by the child exclusively.
 
 Clarify the comment: say that we set the parent-side end of the socket
 pair to non-blocking.
 
 This clarification will play a role in a subsequent patch.
 
 Signed-off-by: Laszlo Ersek <lersek(a)redhat.com>
 ---
 
 Notes:
     context:-U5
 
  generator/states-connect.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)
 
 diff --git a/generator/states-connect.c b/generator/states-connect.c
 index 8a286e6630ff..95a96b9114c6 100644
 --- a/generator/states-connect.c
 +++ b/generator/states-connect.c
 @@ -281,11 +281,11 @@  CONNECT_COMMAND.START:
    /* Parent. */
    close (sv[1]);
  
    h->pid = pid;
  
 -  /* The socket must be set to non-blocking only in the parent,
 +  /* Only the parent-side end of the socket pair must be set to non-blocking,
     * because the child may not be expecting a non-blocking socket.
     */
    flags = fcntl (sv[0], F_GETFL, 0);
    if (flags == -1 ||
        fcntl (sv[0], F_SETFL, flags|O_NONBLOCK) == -1) { 
Reviewed-by: Richard W.M. Jones <rjones(a)redhat.com>
-- 
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