File access

[JD]

Thanks for answering,

No, the data was writing into the file when the subprocess was
runing.

For example, every second it will write something into the file.

I tried to run another python program aside and it sucessfully read
the file when the subprocess was runing.

JD

On Aug 2, 11:00 am, Adrian Petrescu <apetr... at uwaterloo.ca> wrote:
> On Aug 2, 12:41 pm, JD <Jiandong... at gmail.com> wrote:
>
>
>
> > Hi,
>
> > What I am trying to do is to run a subprocess on another machine using
> > subprocess.Popen, this subprocess contuinue writing something into a
> > file when it is runing.
>
> > After submit this subprocess, I tried to open the file and readlines()
> > in the loop (with a delay) in the loop) when the subprocess was
> > runing.
>
> > The problem is I could not get anything untill the subprocess
> > finished.
>
> > I also tried to run another python programm when the subprocess is
> > runing, I could get what I want.
>
> > Does anyone know why? Thanks!
>
> > JD
>
> Could the problem be that the subprocess only flushes the output
> buffer when it terminates, and so until the subprocess "finishes", as
> you say, the file is empty because the data is still in the buffer?
> Trying throwing some flushes into the code and see if it helps.
>
> Or am I misunderstanding your question?