sys.stdout.write() question

[Gian Mario Tagliaretti]

Hi all,

It is (I hope) a simple question,
I cannot figure out why sys.stdout.write() doesn't print immediatly the first
text in the small example below, but before it process the code in between
and then print both lines in one time.

#!/usr/bin/env python
import sys, time
sys.stdout.write('write ')
time.sleep(3)
sys.stdout.write('this\n')

if you try to run this, before it will wait 3 seconds and then print "write
this" in one time.

If I put \n here :

sys.stdout.write('write \n')

it work properly but I would like to print the text in one row.

thanks to all
Mario

[Reinhold Birkenfeld]

Gian Mario Tagliaretti wrote:

Hi all,

It is (I hope) a simple question,
I cannot figure out why sys.stdout.write() doesn't print immediatly the first
text in the small example below, but before it process the code in between
and then print both lines in one time.

#!/usr/bin/env python
import sys, time
sys.stdout.write('write ')
time.sleep(3)
sys.stdout.write('this\n')

if you try to run this, before it will wait 3 seconds and then print "write
this" in one time.

Apparently the stdout "file" is buffered on your system. Have a look at
file.flush() which could help you out.

Reinhold

--
Wenn eine Linuxdistribution so wenig brauchbare Software wie Windows
mitbrächte, wäre das bedauerlich. Was bei Windows der Umfang eines
"kompletten Betriebssystems" ist, nennt man bei Linux eine Rescuedisk.
-- David Kastrup in de.comp.os.unix.linux.misc

[Ivan Voras]

Gian Mario Tagliaretti wrote:

#!/usr/bin/env python
import sys, time
sys.stdout.write('write ')
time.sleep(3)
sys.stdout.write('this\n')

if you try to run this, before it will wait 3 seconds and then print "write
this" in one time.

If I put \n here :

sys.stdout.write('write \n')

it work properly but I would like to print the text in one row.

It line-buffers the output. If you need to print something that is not 'a
whole line', use sys.stdout.flush() after the ...write()

[Peter Hansen]

Gian Mario Tagliaretti wrote:

It is (I hope) a simple question,
I cannot figure out why sys.stdout.write() doesn't print immediatly the first
text in the small example below, but before it process the code in between
and then print both lines in one time.

sys.stdout.flush(). Flush on a file object pushes out all the data
that has been buffered to that point.

-Peter