From: Namhyung Kim <namhyung@kernel.org>
Date: Mon, 7 Nov 2022 21:33:08 +0000 (-0800)
Subject: perf stat: Clear screen only if output file is a tty
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=81a02c6577ecfee7056ccafbd028984d0d670c0c;p=linux.git

perf stat: Clear screen only if output file is a tty

The --interval-clear option makes perf stat to clear the terminal at
each interval.  But it doesn't need to clear the screen when it saves
to a file.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Link: https://lore.kernel.org/r/20221107213314.3239159-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---

diff --git a/tools/perf/util/stat-display.c b/tools/perf/util/stat-display.c
index 576283afa319c..ccb804546d5a3 100644
--- a/tools/perf/util/stat-display.c
+++ b/tools/perf/util/stat-display.c
@@ -890,7 +890,7 @@ static void print_interval(struct perf_stat_config *config,
 	FILE *output = config->output;
 	static int num_print_interval;
 
-	if (config->interval_clear)
+	if (config->interval_clear && isatty(fileno(output)))
 		puts(CONSOLE_CLEAR);
 
 	if (!config->iostat_run && !config->json_output)