[PATCH 4/4] perf ftrace: Use pager for displaying result

[Namhyung Kim]

It's convenient to use pager when seeing many lines of result.

Note that setup_pager() should be called after perf_evlist__
prepare_workload() since they can interfere each other regarding
shared stdio streams.

Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
 tools/perf/builtin-ftrace.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c
index d5b566ed7178..6087295f8827 100644
--- a/tools/perf/builtin-ftrace.c
+++ b/tools/perf/builtin-ftrace.c
@@ -195,6 +195,7 @@ static int __cmd_ftrace(struct perf_ftrace *ftrace, int argc, const char **argv)
 	signal(SIGINT, sig_handler);
 	signal(SIGUSR1, sig_handler);
 	signal(SIGCHLD, sig_handler);
+	signal(SIGPIPE, sig_handler);
 
 	if (reset_tracing_files(ftrace) < 0)
 		goto out;
@@ -247,6 +248,8 @@ static int __cmd_ftrace(struct perf_ftrace *ftrace, int argc, const char **argv)
 		goto out_close_fd;
 	}
 
+	setup_pager();
+
 	perf_evlist__start_workload(ftrace->evlist);
 
 	while (!done) {
-- 
2.11.1