Prevent string being printed python

Question

I'm using some library and I can't edit its source. There is a function in the library that I have to call, and when I call it, it makes this file that I want; however, at the same time, it prints this warning to the screen hundreds of times. The warning is always the same.

Warning during export : no corresponding GDSII layer found for process and purpose

This is kind of annoying and makes me printing anything to stdout/stderr useless, because it just gets flooded with this silly warning.

I know how to redirect stdout/stderr by simply assigning them a different file. Is it possible to simply check what will be written to stdout/stderr, discard it if it's that string, otherwise, print it?

Yes, it's not my library, and it's running from the owners server. It's also in the process of being commericialised. — Jean-Luc
– Jean-Luc, Commented Oct 9, 2015 at 1:11
I recommend letting the owners know that their library has some extraneous print statements/calls, and no one likes a chatty library. — TigerhawkT3
– TigerhawkT3, Commented Oct 9, 2015 at 1:17

cdonts · Accepted Answer · 2015-10-10 00:09:15Z

8

I would use something like...

3.x

import sys
from _io import TextIOWrapper

class StdoutFilter(TextIOWrapper):

    def __init__(self, stdout):
        super().__init__(stdout)
        self.stdout = stdout

    def write(self, output):
        if output != "don't write this":
            self.stdout.write(output)

sys.stdout = StdoutFilter(sys.stdout)

print("hello, world!")
print("don't write this")

sys.stdout = sys.__stdout__

2.x

from StringIO import StringIO

class StdoutFilter(StringIO):

    def __init__(self, stdout):
        StringIO.__init__(self, stdout)
        self.stdout = stdout

Hope it helps!

edited Oct 10, 2015 at 0:09

answered Oct 9, 2015 at 1:08

cdonts

9,7116 gold badges53 silver badges78 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Jean-Luc Over a year ago

Thanks for that, certainly does help! There seems to be an odd problem getting it to work for python 2.7. I get the error: attribute error: readable at super().__init__(stdout). Any ideas why? A Google search didn't seem to reveal much.

cdonts Over a year ago

@Jean-Luc You're welcome. See the update for the 2.x version!

Collectives™ on Stack Overflow

Prevent string being printed python

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related