See attached trivial patch which brings trace a bit closer to strace.
I've never published a patch to the Kernel yet, I hope it's OK as-is. I can
amend it at will if you have any requests to the style.
Cheers
--
Milian Wolff
[email protected]
http://milianw.de
>From 188476d65bab17ad99f5bdf65294160ef2d5f49b Mon Sep 17 00:00:00 2001
From: Milian Wolff <[email protected]>
Date: Tue, 4 Aug 2015 18:30:52 +0200
Subject: [PATCH] perf: let trace write to stderr by default
Without this patch, it is cumbersome to read the trace output
but ignoring the normal, potentially verbose, output of the debuggee.
One common example is doing something like the following:
perf trace -s find /tmp > /dev/null
Without this patch, the trace summary will be lost. Now, it will
still be printed at the end. This behavior is also applied by strace.
---
tools/perf/builtin-trace.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index 39ad4d0..d183d88 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -2778,7 +2778,7 @@ int cmd_trace(int argc, const char **argv, const char *prefix __maybe_unused)
.mmap_pages = UINT_MAX,
.proc_map_timeout = 500,
},
- .output = stdout,
+ .output = stderr,
.show_comm = true,
.trace_syscalls = true,
};
--
2.5.0
