Silence buildbot warnings about unused results

This ignores the results of the two writes in sigint handlers even
harder than before.

While my libc lacks the declarations that trigger these warnings, this
can be tested by adding the following to notmuch.h:

__attribute__((warn_unused_result))
ssize_t write(int fd, const void *buf, size_t count);

1 files changed, 6 insertions, 1 deletions

diff --git a/notmuch-tag.c b/notmuch-tag.c
index 292c5da..44fd61f 100644
--- a/notmuch-tag.c
+++ b/notmuch-tag.c
@@ -26,7 +26,12 @@ static void
 handle_sigint (unused (int sig))
 {
     static char msg[] = "Stopping...         \n";
-    (void) write(2, msg, sizeof(msg)-1);
+
+    /* This write is "opportunistic", so it's okay to ignore the
+     * result.  It is not required for correctness, and if it does
+     * fail or produce a short write, we want to get out of the signal
+     * handler as quickly as possible, not retry it. */
+    IGNORE_RESULT (write (2, msg, sizeof(msg)-1));
     interrupted = 1;
 }