From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mout.kundenserver.de ([212.227.126.130]:53467 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752296AbcGSJ00 (ORCPT ); Tue, 19 Jul 2016 05:26:26 -0400 From: Arnd Bergmann To: Wim Van Sebroeck Cc: Arnd Bergmann , Guenter Roeck , Jonathan Corbet , Timur Tabi , linux-watchdog@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] Documentation/watchdog: check return value for magic close Date: Tue, 19 Jul 2016 11:24:50 +0200 Message-Id: <20160719092522.6397-1-arnd@arndb.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-watchdog-owner@vger.kernel.org List-Id: linux-watchdog@vger.kernel.org A recent commit added a write to the watchdog test code for doing the "magic close", but that caused a compile-time warning: Documentation/watchdog/src/watchdog-test.c: In function ‘main’: Documentation/watchdog/src/watchdog-test.c:94:5: warning: ignoring return value of ‘write’, declared with attribute warn_unused_result [-Wunused-result] This changes the code to print a runtime warning if the write fails. Fixes: 5a2d3de19602 ("Documentation/watchdog: add support for magic close to watchdog-test") Signed-off-by: Arnd Bergmann --- Documentation/watchdog/src/watchdog-test.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/Documentation/watchdog/src/watchdog-test.c b/Documentation/watchdog/src/watchdog-test.c index c69153913722..52eea54649ab 100644 --- a/Documentation/watchdog/src/watchdog-test.c +++ b/Documentation/watchdog/src/watchdog-test.c @@ -2,6 +2,7 @@ * Watchdog Driver Test Program */ +#include #include #include #include @@ -35,9 +36,13 @@ static void keep_alive(void) static void term(int sig) { - write(fd, &v, 1); + int ret = write(fd, &v, 1); + close(fd); - printf("\nStopping watchdog ticks...\n"); + if (ret < 0) + printf("\nStopping watchdog ticks failed (%d)...\n", errno); + else + printf("\nStopping watchdog ticks...\n"); exit(0); } @@ -45,6 +50,7 @@ int main(int argc, char *argv[]) { int flags; unsigned int ping_rate = 1; + int ret; setbuf(stdout, NULL); @@ -91,7 +97,9 @@ int main(int argc, char *argv[]) sleep(ping_rate); } end: - write(fd, &v, 1); + ret = write(fd, &v, 1); + if (ret < 0) + printf("Sopping watchdog ticks failed (%d)...\n", errno); close(fd); return 0; } -- 2.9.0