fork, exec, and disown

[Benoit Dejean]

hello, i have a question about forking processes

atm, i have some code which i want to rewrite

	os.system("cd ~ && exec " + cmd + " & disown")


i want to remove this os.system call


def fork_exec_disown(cmd, dir="~"):

    if os.fork()==0:

        os.chdir(os.path.expanduser(dir))
        os.setsid()
        os.umask(0)
    
        if os.fork():
           sys.exit(0)

        cmd = cmd.split()
        os.execvp(cmd[0], cmd)
        
  
      
but i am not sure that this have the same behaviour.

is the second fork needed ? i think so to detach the spawn process
i have found in the os doc, os.setsid, i think i have to use it.


am i going wrong or is this simple


def fork_exec_disown(cmd, dir="~"):

    if os.fork()==0:
        os.chdir(os.path.expanduser(dir))   
        cmd = cmd.split()
        os.execvp(cmd[0], cmd) 
        
a good replacement for my os.system call

thank you