print without newline "halts" program execution

[Karlo Lozovina]

Consider this short script:

---
from time import time, sleep

st = time()
print 'Start: %f, ' % st,
sleep(10)
sp = time()
print 'Stop: %f, Duration: %f' % (sp, (st - sp))
---

On my environment (Linux, py24), when run, Python first waits 10s, and
then produces the entire output. How, can I make it print first part
('Start: %f, '), then wait 10s, and then append (WITHOUT NEWLINE) that
second print statement?

I'm writting a script with lot of output which has to go on the same line,
but I don't want to wait for it to end to see output, I just want it to
print parts as it's finished with them.

Using sys.stdout.writ e() produces the same behavior, so what can I do?

Thanks a lot in advance.

--
_______ Karlo Lozovina - Mosor
| | |.-----.-----. web: http://www.mosor.net || ICQ#: 10667163
| || _ | _ | Parce mihi domine quia Dalmata sum.
|__|_|__||_____ |_____|

[Jay Parlar]

Re: print without newline "halts&quo t; program execution


On Apr 13, 2006, at 5:57 PM, Karlo Lozovina wrote:
[color=blue]
> Consider this short script:
>
> ---
> from time import time, sleep
>
> st = time()
> print 'Start: %f, ' % st,
> sleep(10)
> sp = time()
> print 'Stop: %f, Duration: %f' % (sp, (st - sp))
> ---
>
> On my environment (Linux, py24), when run, Python first waits 10s, and
> then produces the entire output. How, can I make it print first part
> ('Start: %f, '), then wait 10s, and then append (WITHOUT NEWLINE) that
> second print statement?
>
> I'm writting a script with lot of output which has to go on the same
> line,
> but I don't want to wait for it to end to see output, I just want it to
> print parts as it's finished with them.
>
> Using sys.stdout.writ e() produces the same behavior, so what can I do?
> from time import time, sleep
>
>[/color]

Your problem is that the 'print' statement is sending the text to
sys.stdout, and sys.stdout is buffered.

There are other ways to do this, but try this:

from time import time, sleep
import sys

st = time()
print 'Start: %f,'% st,
sys.stdout.flus h()
sleep(10)
sp = time()
print 'Stop: %f, Duration: %f' % (sp, (st-sp))


Jay P.

[Karlo Lozovina]

Re: print without newline "halts&quo t; program execution

Jay Parlar <jparlar@cogeco .ca> wrote in
news:mailman.45 37.1144976780.2 7775.python-list@python.org :
[color=blue]
> Your problem is that the 'print' statement is sending the text to
> sys.stdout, and sys.stdout is buffered.[/color]

I thought it was something like this, but I couldn't find it in the docs :
(.
[color=blue]
> print 'Start: %f,'% st,
> sys.stdout.flus h()
> sleep(10)
> sp = time()
> print 'Stop: %f, Duration: %f' % (sp, (st-sp))[/color]

This works excellent, *thank* you.
[color=blue]
> There are other ways to do this, but try this:[/color]

And for purely academical purposes, what are those other ways to do it?
I'm curious :).

--
_______ Karlo Lozovina - Mosor
| | |.-----.-----. web: http://www.mosor.net || ICQ#: 10667163
| || _ | _ | Parce mihi domine quia Dalmata sum.
|__|_|__||_____ |_____|