[GRASS-dev] python and GRASS_MESSAGE_FORMAT
dca.gis at gmail.com
Sat Nov 25 21:02:38 EST 2006
Hi Jachym. This looks like a buffered vs. unbuffered stream problem.
Looking at lib/gis/percent.c, the output of (the G_percent calls of)
r.los should flush at every write so if you try to popen in unbuffered
mode, you should get what you need: try os.popen("your_cmd","r",0).
On 11/25/06, Jachym Cepicky <jachym.cepicky at centrum.cz> wrote:
> On Sat, Nov 25, 2006 at 06:56:14PM +0000, Glynn Clements wrote:
> > The documentation for the readlines() method says:
> > readlines([sizehint])
> > Read until EOF using readline() and return a list containing the
> > lines thus read. If the optional sizehint argument is present,
> > instead of reading up to EOF, whole lines totalling approximately
> > sizehint bytes (possibly after rounding up to an internal buffer
> > size) are read. Objects implementing a file-like interface may
> > choose to ignore sizehint if it cannot be implemented, or cannot
> > be implemented efficiently.
> > The "until EOF" means that it isn't going to return until the command
> > has completed.
> > > Could somebody help me, how to do it? Could you point me to tcl code,
> > > which must solve this problem too?
> > Looking at the Python docs, you probably want something like:
> > f = os.popen("r.los in=elevation.dem out=tmp 2>&1")
> > try:
> > for line in f:
> > print line
> > finally:
> > f.close()
> thanks, Glynn, but it does not seem to work - or it works the same way,
> like readlines() does.
> I have in the script:
> import os
> f = os.popen("r.los --o in=elevation.dem out=tmp \
> coordinate=603067.6875,4925297.0625 max_dist=10000 2>&1")
> for line in f:
> print line
> result is, lines are printed. but _after_ r.los finished it's
> do I understand something wrong?
> Jachym Cepicky
> e-mail: jachym.cepicky at centrum.cz
> URL: http://les-ejk.cz
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