test_ok1/py/misc/stdoutcapture.py

74 lines
2.3 KiB
Python

"""
A quick hack to capture stdout/stderr.
"""
import os, sys
class Capture:
def __init__(self, mixed_out_err = False):
"Start capture of the Unix-level stdout and stderr."
if (not hasattr(os, 'tmpfile') or
not hasattr(os, 'dup') or
not hasattr(os, 'dup2') or
not hasattr(os, 'fdopen')):
self.dummy = 1
else:
self.dummy = 0
# make new stdout/stderr files if needed
self.localoutfd = os.dup(1)
self.localerrfd = os.dup(2)
if hasattr(sys.stdout, 'fileno') and sys.stdout.fileno() == 1:
self.saved_stdout = sys.stdout
sys.stdout = os.fdopen(self.localoutfd, 'w', 1)
else:
self.saved_stdout = None
if hasattr(sys.stderr, 'fileno') and sys.stderr.fileno() == 2:
self.saved_stderr = sys.stderr
sys.stderr = os.fdopen(self.localerrfd, 'w', 0)
else:
self.saved_stderr = None
self.tmpout = os.tmpfile()
if mixed_out_err:
self.tmperr = self.tmpout
else:
self.tmperr = os.tmpfile()
os.dup2(self.tmpout.fileno(), 1)
os.dup2(self.tmperr.fileno(), 2)
def done(self):
"End capture and return the captured text (stdoutfile, stderrfile)."
if self.dummy:
import cStringIO
return cStringIO.StringIO(), cStringIO.StringIO()
else:
os.dup2(self.localoutfd, 1)
os.dup2(self.localerrfd, 2)
if self.saved_stdout is not None:
f = sys.stdout
sys.stdout = self.saved_stdout
f.close()
else:
os.close(self.localoutfd)
if self.saved_stderr is not None:
f = sys.stderr
sys.stderr = self.saved_stderr
f.close()
else:
os.close(self.localerrfd)
self.tmpout.seek(0)
self.tmperr.seek(0)
return self.tmpout, self.tmperr
if __name__ == '__main__':
# test
c = Capture()
try:
os.system('echo hello')
finally:
fout, ferr = c.done()
print 'Output:', `fout.read()`
print 'Error:', `ferr.read()`