hey there, thanks for the guidance. I even tried converting the system call as a perl package. to crosscheck the control flow i gave a logging mechanism to check what all calls came to that module. my pseudo code will look like this: my $r = qx(function_name $arg1 $arg2 $arg3); if i execute function_name $arg1 $arg2 $arg3 in CLI or called from different perl file, it works!!!!