system

system 
list

Executes any program on the system for you. It does exactly the same thing as exec list except that it does a fork first, and then, after the exec , it waits for the exec ed program to complete. That is, it runs the program for you, and returns when it's done, unlike exec , which never returns (if it succeeds). Note that argument processing varies depending on the number of arguments, as described for exec . The return value is the exit status of the program as returned by the wait(2) call. To get the actual exit value, divide by 256. (The lower eight bits are set if the process died from a signal.) See exec .