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 <ler...@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 <rjo...@redhat.com>
--
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