How do I print to console when output is redirected to a file?

Question

I want to write results of some calculations to a file with print and print some other data like progress indication to Windows console so I can see it immediately.

What I write to console is: C:\Users\BoltKey>python program.py < in.txt > out.txt.

Is there a way to overload output redirection and print to console? Or is it just wrong and I should use file functions if I want to print to the console and into files at the same time?

Here is pseudocode:

for i in range(100):
     for j in range(100):
          result = getResult(i, j)
          print result  // print to output file
     consolePrint "progress: " + str(i) + "%"  // print to console

score 1 · Answer 1 · edited May 23 '17 at 12:07

1

You can print to stderr to achieve this (your command line is only redirecting stdout to a file). There are a couple of ways to achieve this, but a good one is found in this SO answer:

    import sys
    from __future__ import print_function

...

    print("Message", file=sys.stderr)

edited May 23 '17 at 12:07

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answered Dec 10 '15 at 00:57

Turn

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score 0 · Accepted Answer · edited May 23 '17 at 10:27

0

Sounds an ugly hack to me.

Just use stderr for displaying progress messages.

edited May 23 '17 at 10:27

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answered Dec 10 '15 at 00:57

Karoly Horvath

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Should add in an example rather than requiring a click. – leewz Dec 10 '15 at 01:57

How do I print to console when output is redirected to a file?

2 Answers2