基于@YinonEhrlich的答案。此变体尝试避免泄漏文件描述符:
import os
import sys
from contextlib import contextmanager
@contextmanager
def stdout_redirected(to=os.devnull):
'''
import os
with stdout_redirected(to=filename):
print("from Python")
os.system("echo non-Python applications are also supported")
'''
fd = sys.stdout.fileno()
##### assert that Python and C stdio write using the same file descriptor
####assert libc.fileno(ctypes.c_void_p.in_dll(libc, "stdout")) == fd == 1
def _redirect_stdout(to):
sys.stdout.close() # + implicit flush()
os.dup2(to.fileno(), fd) # fd writes to 'to' file
sys.stdout = os.fdopen(fd, 'w') # Python writes to fd
with os.fdopen(os.dup(fd), 'w') as old_stdout:
with open(to, 'w') as file:
_redirect_stdout(to=file)
try:
yield # allow code to be run with the redirected stdout
finally:
_redirect_stdout(to=old_stdout) # restore stdout.
# buffering and flags such as
# CLOEXEC may be different