terminal.py 1.0 KB

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  1. # Copyright 2019 Google
  2. #
  3. # Licensed under the Apache License, Version 2.0 (the "License");
  4. # you may not use this file except in compliance with the License.
  5. # You may obtain a copy of the License at
  6. #
  7. # http://www.apache.org/licenses/LICENSE-2.0
  8. #
  9. # Unless required by applicable law or agreed to in writing, software
  10. # distributed under the License is distributed on an "AS IS" BASIS,
  11. # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12. # See the License for the specific language governing permissions and
  13. # limitations under the License.
  14. import subprocess
  15. import threading
  16. _lock = threading.Lock()
  17. _columns = None
  18. def columns():
  19. """Returns the number of columns in the terminal's display."""
  20. global _columns
  21. with _lock:
  22. if _columns is None:
  23. _columns = _find_terminal_columns()
  24. return _columns
  25. def _find_terminal_columns():
  26. try:
  27. result = subprocess.check_output(['tput', 'cols'])
  28. return int(result.rstrip())
  29. except subprocess.CalledProcessError:
  30. return 80