what is the diffrence between subprocess and execfile

Question

Could you tell me what is difference between execfile and subprocess . I guess these two commands work same .

but when I use Execfile() there is no problem getting variable from another .py file . but when I try to use subprocess.Popen() there is an error like ""NameError: global name 'xy' is not defined""

what provide to get that error ? and why when I use Popen command that gives error and execfile works fine ..

Answer 1

execfile and popen are very different commands.

Execfile allows to to pull in another file of python and run it in the same environment as your main script.

Popen allows you to spawn a subprocess of anything you like, not just python. It's a 'blackbox' so your chances of seeing what's happening in it is limited to the exit value it posts, or scanning it's STDERR and STDOUT

If you really want to run your second script standalone use popen)

If you want to import your other python code and embed it in your file (use execfile, if you must).