The following are examples of sh_syscalls.d. This is a simple script to count Ruby methods and system calls. Here we trace an example program - Code/Ruby/func_abc.rb # rb_syscalls.d -c ./func_abc.rb Tracing... Hit Ctrl-C to end. Function A Function B Function C Calls for PID 146493, FILE TYPE NAME COUNT func_abc.rb method Object::func_a 1 func_abc.rb method Object::func_b 1 func_abc.rb method Object::func_c 1 func_abc.rb syscall getpid 1 func_abc.rb syscall getrlimit 1 func_abc.rb syscall getrlimit64 1 func_abc.rb syscall mmap 1 func_abc.rb syscall munmap 1 func_abc.rb syscall rexit 1 func_abc.rb syscall schedctl 1 func_abc.rb syscall sigpending 1 func_abc.rb syscall sysconfig 1 func_abc.rb syscall sysi86 1 func_abc.rb syscall write 1 func_abc.rb syscall llseek 2 func_abc.rb syscall read 2 func_abc.rb syscall setcontext 2 func_abc.rb method IO::write 3 func_abc.rb method Module::method_added 3 func_abc.rb method Object::print 3 func_abc.rb method Object::sleep 3 func_abc.rb syscall fstat64 3 func_abc.rb syscall getgid 3 func_abc.rb syscall getuid 3 func_abc.rb syscall ioctl 3 func_abc.rb syscall pollsys 3 func_abc.rb syscall close 4 func_abc.rb syscall lwp_sigmask 4 func_abc.rb syscall open64 4 func_abc.rb syscall gtime 6 func_abc.rb syscall sigaction 12 func_abc.rb syscall brk 56 While tracing, three user-defined functions were called - func_a, func_b and func_c. There were 3 instances of the IO::write method being called. There were also many system calls made, including 56 brk()'s, and 12 sigaction()'s. This script can provide an insight to how a Ruby program is interacting with the system, by providing methods and system calls in the same output.