POSIX Process Calls


 # fork -- create a (duplicate) process
if os.fork() == 0:
   print "in child"
else:
   print "in parent"

 # exec -- overlay the process with another executable
os.execl("/bin/more", "more", "foo.txt")  # note: no 0 terminator
os.execvp(sys.argv[0], sys.argv)

 # sleep -- put process to sleep for specified time
time.sleep(n)

 # exit -- terminate process
sys.exit(0)

 # wait -- wait for termination of child
pid, status = wait()  # no arguments, returns a pair of values
print "Returned status:", status/256

 # getpid -- return process id
myId = os.getpid()