ftracetest: Fix instance test to use proper shell command for pids

rostedt · rostedt · commit 9a154c8911e3 · 2016-02-19T12:11:21.000-05:00
The ftracetest instance test used parsing of the "jobs" output to find the pid of the subshell that is executed previously. But this is not portable to all major shells that may run these tests. The proper way to get the pid of the subshell is the shell command "$!". This will return the pid of the previously executed command. Use that instead, otherwise the test does not work in all environments. Link: http://lkml.kernel.org/r/20151211143617.65f4d7a1@gandalf.local.home Reported-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/tools/testing/selftests/ftrace/test.d/instances/instance.tc b/tools/testing/selftests/ftrace/test.d/instances/instance.tc
@@ -39,28 +39,23 @@ instance_slam() {
 }
 
 instance_slam &
-x=`jobs -l`
-p1=`echo $x | cut -d' ' -f2`
+p1=$!
 echo $p1
 
 instance_slam &
-x=`jobs -l | tail -1`
-p2=`echo $x | cut -d' ' -f2`
+p2=$!
 echo $p2
 
 instance_slam &
-x=`jobs -l | tail -1`
-p3=`echo $x | cut -d' ' -f2`
+p3=$!
 echo $p3
 
 instance_slam &
-x=`jobs -l | tail -1`
-p4=`echo $x | cut -d' ' -f2`
+p4=$!
 echo $p4
 
 instance_slam &
-x=`jobs -l | tail -1`
-p5=`echo $x | cut -d' ' -f2`
+p5=$!
 echo $p5
 
 ls -lR >/dev/null
