[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

What's wrong on using Popen's communicate method?

On Thu, 04 Jul 2019 10:36:36 +1000, Cameron Simpson wrote:

> On 03Jul2019 16:57, Jach Fong <jfong at> wrote:
>>I have the below. I expect to see 'abcd' showing in the notepad window:
>>import subprocess as sp
>>p0 = sp.Popen('notepad.exe', stdin=sp.PIPE)
>>But nothing happens. The notepad is completely empty. What have I missed?
>>PS. I am using python 3.4 on Windows Vista
> Well I am not a Windows person, but in most GUI environments a desktop 
> app such as Notepad does not read from its standard input - it reads 
> keyboard stuff though the GUI interface instead. So it is ignoring your 
> input data - this approach will generally fail with any desktop app on 
> any platform.
> You may need to investigate generating synthetic keystrokes somehow.
> Or alternatively write your data to a text file and hand the name of the 
> text file to notepad as a file to edit.
> Cheers,
> Cameron Simpson <cs at>

I block googlegroups so I don't see the original post.  I am
talking to the OP.

Take a look at the SendKeys module.

<Wildman> GNU/Linux user #557453
The cow died so I don't need your bull!