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Unbuffered stdout/auto-flush

Hi, is there any way to get unbuffered stdout/stderr without relying on
the -u flag to python or calling .flush() on each print (including
indirect hacks like replacing sys.stdout with a wrapper that succeeds
each write() with a flush())? Thanks in advance!
--
Yang Zhang
http://www.mit.edu/~y_z/
Jun 27 '08 #1
1 4612
On Jun 21, 12:29 pm, Yang Zhang <yanghates...@gmail.comwrote:
Hi, is there any way to get unbuffered stdout/stderr without relying on
the -u flag to python or calling .flush() on each print (including
indirect hacks like replacing sys.stdout with a wrapper that succeeds
each write() with a flush())? Thanks in advance!
I think the only way is to reopen the stdout file descriptor:

import sys
import os

# reopen stdout file descriptor with write mode
# and 0 as the buffer size (unbuffered)
sys.stdout = os.fdopen(sys.stdout.fileno(), 'w', 0)

print "unbuffered text"

Sebastian
Jun 27 '08 #2

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