I have the following situation, I want to monitor the system calls on Android phones so I made an script to do that. With Android Emulator works perfectly (writes the traces of the application in a specific file on my Ubuntu). The problem is when I attach a real phone to analyze it, it says the following in the result file:

ptrace attach failed: Operation not permitted

I'm using this code to get it, but I don't understand why it works on the emulator and not in the rooted real device.

This is the comand I use in perl:

system("$dirTools/adb -s $Device shell strace -p $PID[1]>$dirRecordDataSet/$Date/$appName &");

Any suggestion? Thanks in advance