[ltt-dev] [UST PATCH] Fix up all use of /dev/stderr for portability to busybox /bin/sh

Jason Wessel jason.wessel at windriver.com
Tue Apr 12 15:11:36 EDT 2011


The typical shell on a small embedded target using busybox does
not have support for /dev/stderr.  A more portable way to send
output to stderr with echo is to redirect stdout to stderr with
1>&2.

In the usttrace script it did something that was effectively
a NOP.  The result of echo "" 2>/dev/stderr is not actually
going to send anything to stderr because the echo is going
to write to stdout.  This case was also fixed.

Signed-off-by: Jason Wessel <jason.wessel at windriver.com>
---
 tests/test_functions.sh         |    2 +-
 tests/trace_matches             |    4 ++--
 tests/valgrind_ust-consumerd.sh |    2 +-
 usttrace                        |   26 +++++++++++++-------------
 4 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/tests/test_functions.sh b/tests/test_functions.sh
index 79ade73..c4e913b 100644
--- a/tests/test_functions.sh
+++ b/tests/test_functions.sh
@@ -77,7 +77,7 @@ function trace_matches() {
 	LTTV_TRACE_PREFIX=""
 
     else
-	echo "$0: No lttv found. Edit \$RUNLTTV to point to your lttv source directory or \$LTTV to you lttv executable." >/dev/stderr
+	echo "$0: No lttv found. Edit \$RUNLTTV to point to your lttv source directory or \$LTTV to you lttv executable." 1>&2
 	exit 1;
 
     fi
diff --git a/tests/trace_matches b/tests/trace_matches
index 17a65f8..da3d954 100755
--- a/tests/trace_matches
+++ b/tests/trace_matches
@@ -1,7 +1,7 @@
 #!/bin/bash
 
 function error() {
-	echo "$0: $@" >/dev/stderr
+	echo "$0: $@" 1>&2
 }
 
 function usage() {
@@ -43,7 +43,7 @@ elif [ -x "$(dirname `readlink -f $0`)/../../lttv/runlttv" ]; then
 	LTTV_TRACE_PREFIX=""
 
 else
-	echo "$0: No lttv found. Edit \$RUNLTTV to point to your lttv source directory or \$LTTV to you lttv executable." >/dev/stderr
+	echo "$0: No lttv found. Edit \$RUNLTTV to point to your lttv source directory or \$LTTV to you lttv executable." 1>&2
 	exit 1;
 
 fi
diff --git a/tests/valgrind_ust-consumerd.sh b/tests/valgrind_ust-consumerd.sh
index 856808b..7dd6668 100755
--- a/tests/valgrind_ust-consumerd.sh
+++ b/tests/valgrind_ust-consumerd.sh
@@ -25,7 +25,7 @@ source $TESTDIR/tap.sh
 starttest "ust-consumerd valgrind check"
 
 if ! which valgrind > /dev/null; then
-    echo "$0: Valgrind not found on the system." >/dev/stderr
+    echo "$0: Valgrind not found on the system." 1>&2
     exit 1;
 fi
 
diff --git a/usttrace b/usttrace
index af80faf..e76dae7 100755
--- a/usttrace
+++ b/usttrace
@@ -4,7 +4,7 @@
 # Distributed under the GPLv2.
 
 error() {
-	echo "$0: error: $1" 2>/dev/stderr
+	echo "$0: error: $1" 1>&2
 }
 
 sighandler() {
@@ -45,18 +45,18 @@ fi
 BASE_TRACE_DIR="${HOME}/.usttraces"
 
 usage() {
-	echo "usage:  $0 OPTIONS COMMAND" 2>/dev/stderr
-	echo "" 2>/dev/stderr
-	echo "Options:" 2>/dev/stderr
-	echo "    -l    Runtime link with UST library." 2>/dev/stderr
-	echo "          (Needed only if program was not linked at compile time with libust.)" 2>/dev/stderr
-	echo "    -L    Add path to ust libraries to LD_LIBRARY_PATH." 2>/dev/stderr
-	echo "    -m    Instrument malloc calls." 2>/dev/stderr
-	echo "    -f    Also trace forked processes." 2>/dev/stderr
-	echo "    -s    Use system-wide daemon instead of creating one for this session." 2>/dev/stderr
-	echo "    -S    Specify the subbuffer size." 2>/dev/stderr
-	echo "    -N    Specify the number of subbuffers." 2>/dev/stderr
-	echo "    -o    Output directory of the trace." 2>/dev/stderr
+	echo "usage:  $0 OPTIONS COMMAND" 1>&2
+	echo "" 1>&2
+	echo "Options:" 1>&2
+	echo "    -l    Runtime link with UST library." 1>&2
+	echo "          (Needed only if program was not linked at compile time with libust.)" 1>&2
+	echo "    -L    Add path to ust libraries to LD_LIBRARY_PATH." 1>&2
+	echo "    -m    Instrument malloc calls." 1>&2
+	echo "    -f    Also trace forked processes." 1>&2
+	echo "    -s    Use system-wide daemon instead of creating one for this session." 1>&2
+	echo "    -S    Specify the subbuffer size." 1>&2
+	echo "    -N    Specify the number of subbuffers." 1>&2
+	echo "    -o    Output directory of the trace." 1>&2
 }
 
 while getopts ":hlLmfsWS:N:o:" options; do
-- 
1.7.1





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