unbuffered partial line output

[lynx]

i'm trying to print half a line of status message and have it output to
the screen (and/or file object) with the cursor waiting at the end of the
output. later on, i'll finish up that line with the remaining half-line's
worth of further status output, but in between goes several minutes' worth
of processing.

unfortunately, all the "obvious" ways of printing-without-a-final-\n-
implied seem like they run into buffering issues of some sort - no part of
the line will be output until the second half is done, leaving me to wait
until my processing is completed to see the half-line that's supposed to
tell me it just started.

is there some attribute of sys.stdout i'm supposed to set to get my output
flushed directly to screen, or some other method of outputting text
that'll get around this? i can't seem to find any mention about output
buffering in the documentation. or am i doing something completely worng
without knowing it?

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