[PATCH] perf stat: fix output selection introduced in 56f3bae7

[PATCH] perf stat: fix output selection introduced in 56f3bae7

[Łukasz Stelmach]

56f3bae7 makes perf require either --output or --log-fd. Without them
perf exited after erroneously trying to open stdout (file descriptor 0
by default) for writing.

Signed-off-by: Łuaksz Stelmach <l.stelmach@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
---
 tools/perf/builtin-stat.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index c941bb6..c0f8129 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -196,7 +196,7 @@ static bool			csv_output			= false;
 static bool			group				= false;
 static const char		*output_name			= NULL;
 static FILE			*output				= NULL;
-static int			output_fd;
+static int			output_fd			= -1;
 
 static volatile int done = 0;
 
@@ -1146,7 +1146,7 @@ int cmd_stat(int argc, const char **argv, const char *prefix __used)
 	if (output_name && strcmp(output_name, "-"))
 		output = NULL;
 
-	if (output_name && output_fd) {
+	if (output_name && output_fd >= 0) {
 		fprintf(stderr, "cannot use both --output and --log-fd\n");
 		usage_with_options(stat_usage, options);
 	}
@@ -1161,7 +1161,7 @@ int cmd_stat(int argc, const char **argv, const char *prefix __used)
 		}
 		clock_gettime(CLOCK_REALTIME, &tm);
 		fprintf(output, "# started on %s\n", ctime(&tm.tv_sec));
-	} else if (output_fd != 2) {
+	} else if (output_fd >= 0) {
 		mode = append_file ? "a" : "w";
 		output = fdopen(output_fd, mode);
 		if (!output) {
-- 
1.7.9.5

Re: [PATCH] perf stat: fix output selection introduced in 56f3bae7

[Łukasz Stelmach]

Łukasz Stelmach <l.stelmach@samsung.com> writes:

> 56f3bae7 makes perf require either --output or --log-fd. Without them
> perf exited after erroneously trying to open stdout (file descriptor 0
> by default) for writing.

It should be "stdin" not "stdout".
-- 
Łukasz Stelmach
Software engineer
Samsung Poland R&D Center

ul. Polna 11, 00-633 Warszawa
http://www.rd.samsung.pl