create a tmp file for system execution

[Eric Texier]

Thanks, building  a string with ; was the best for what I needed.
I started to play with os.tmpnam() etc. and it wasn't really
straightforward.


Donn Cave wrote:

> Quoth Eric Texier <erict at millfilm.co.uk>:
> | I have a py script executing a bunch of os.system in a loop.
> | It is not very fast and I was wondering if it will not be better
> | to recreate a execution file.
> |
> | My 2 questions:
> |
> | 1) what is faster for a big number of call
> ...
> | os.system("csh -c 'source tmpFile' ")
> | os.system("rm -f tmpFile")
>
> You've already gotten some good answers, and you can answer
> your own questions pretty easily just by trying the things
> you propose to do.  Here are two more points:
>
> -  this takes 4 seconds "wall clock" time on my computer:
>      import os
>      import string
>
>      s = ['ls something somethingelse']*2000
>      s.append('exit 17')
>      s = string.join(s, '; ')
>      t = os.system(s)
>
>     (I added the "exit 17" just so I'd have some way to verify that
>      it really did everything.)
>
> -  If you have a file of commands, you don't need to "source" it,
>    you can invoke the shell directly on the file - it's a "script".
>
> -  Never use csh if you can avoid it, it's the worst of shells.
>    The system() function uses "sh", and that's the right choice for
>    most applications.
>
> -  I'm assuming a UNIX platform.
>
>         Donn Cave, donn at u.washington.edu