How to read the first byte of a subprocess’s stdout and then discard the rest in Python?

by

If you’re using Python 3.3+, you can use the DEVNULL special value for stdout and stderr to discard subprocess output.

from subprocess import Popen, DEVNULL

process = Popen(["mycmd", "myarg"], stdout=DEVNULL, stderr=DEVNULL)

Or if you’re using Python 2.4+, you can simulate this with:

import os
from subprocess import Popen

DEVNULL = open(os.devnull, 'wb')
process = Popen(["mycmd", "myarg"], stdout=DEVNULL, stderr=DEVNULL)

However this doesn’t give you the opportunity to read the first byte of stdout.

More Related Contents:

  1. Read streaming input from subprocess.communicate()
  2. How do I use subprocess.Popen to connect multiple processes by pipes?
  3. Passing Variables to Subprocess.Popen
  4. ImageMagick not authorized to convert PDF to an image
  5. How do I hide the console when I use os.system() or subprocess.call()?
  6. How can I run an external command asynchronously from Python?
  7. catching stdout in realtime from subprocess
  8. How to get exit code when using Python subprocess communicate method?
  9. Displaying subprocess output to stdout and redirecting it
  10. Python subprocess.call a bash alias
  11. Pipe subprocess standard output to a variable [duplicate]
  12. Python read from subprocess stdout and stderr separately while preserving order
  13. How do I get all of the output from my .exe using subprocess and Popen?
  14. Is it possible to run function in a subprocess without threading or writing a separate file/script.
  15. What’s a good equivalent to subprocess.check_call that returns the contents of stdout?
  16. Cross-platform subprocess with hidden window
  17. Python read file as stream from HDFS
  18. How to convert an iterable to a stream?
  19. Python subprocess: callback when cmd exits
  20. ‘yes’ reporting error with subprocess communicate()
  21. How do I pass large numpy arrays between python subprocesses without saving to disk?
  22. wait process until all subprocess finish? [duplicate]
  23. OSError: [Errno 8] Exec format error
  24. running a command as a super user from a python script
  25. Run multiple programs sequentially in one Windows command prompt?
  26. how to kill (or avoid) zombie processes with subprocess module
  27. Piping output of subprocess.Popen to files
  28. Cannot find the file specified when using subprocess.call(‘dir’, shell=True) in Python
  29. subprocess.Popen in different console
  30. printing stdout in realtime from a subprocess that requires stdin

Leave a Comment