Suggested-by: Eric Blake <ebl...@redhat.com> Signed-off-by: Markus Armbruster <arm...@redhat.com> Reviewed-by: Eric Blake <ebl...@redhat.com> Message-Id: <1447776349-2344-1-git-send-email-arm...@redhat.com> --- include/qapi/error.h | 17 +++++++++++++++++ 1 file changed, 17 insertions(+)
diff --git a/include/qapi/error.h b/include/qapi/error.h index 6285cf5..1480f59 100644 --- a/include/qapi/error.h +++ b/include/qapi/error.h @@ -76,6 +76,23 @@ * But when all you do with the error is pass it on, please use * foo(arg, errp); * for readability. + * + * Receive and accumulate multiple errors (first one wins): + * Error *err = NULL, *local_err = NULL; + * foo(arg, &err); + * bar(arg, &local_err); + * error_propagate(&err, local_err); + * if (err) { + * handle the error... + * } + * + * Do *not* "optimize" this to + * foo(arg, &err); + * bar(arg, &err); // WRONG! + * if (err) { + * handle the error... + * } + * because this may pass a non-null err to bar(). */ #ifndef ERROR_H -- 2.4.3