[PULL 07/13] qemu-nbd: improve error message for dup2 error

[Eric Blake]

From: "Denis V. Lunev" <den@openvz.org>

This error happens if we are not able to close the pipe to the
parent (to trace errors in the child process) and assign stderr to
/dev/null as required by the daemonizing convention.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Suggested-by: Eric Blake <eblake@redhat.com>
CC: Eric Blake <eblake@redhat.com>
CC: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-ID: <20230906093210.339585-2-den@openvz.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: commit message grammar]
Signed-off-by: Eric Blake <eblake@redhat.com>
---
 qemu-nbd.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/qemu-nbd.c b/qemu-nbd.c
index b47459f781d..e2480061a16 100644
--- a/qemu-nbd.c
+++ b/qemu-nbd.c
@@ -324,7 +324,7 @@ static void *nbd_client_thread(void *arg)
     } else {
         /* Close stderr so that the qemu-nbd process exits.  */
         if (dup2(STDOUT_FILENO, STDERR_FILENO) < 0) {
-            error_report("Could not set stderr to /dev/null: %s",
+            error_report("Could not release pipe to parent: %s",
                          strerror(errno));
             exit(EXIT_FAILURE);
         }
@@ -1181,7 +1181,7 @@ int main(int argc, char **argv)

     if (fork_process) {
         if (dup2(STDOUT_FILENO, STDERR_FILENO) < 0) {
-            error_report("Could not set stderr to /dev/null: %s",
+            error_report("Could not release pipe to parent: %s",
                          strerror(errno));
             exit(EXIT_FAILURE);
         }
-- 
2.41.0