[GRASS-dev] GRASS and QGIS on Win32, testing etc.

Glynn Clements glynn at gclements.plus.com
Mon May 21 23:05:34 EDT 2007

Moritz Lennert wrote:

> > 1. The DBF driver deadlocks randomly!
> > Any GRASS module that needs to access the attribute table (DBF format)
> > of a vector map is prone to this: E.g. I tried running v.out.ogr on a
> > map with ca. 3000 points repeatedly. Out of ten runs, 2 or 3 deadlock at
> > a random point. The task manager shows that v.out.ogr is sleeping with
> > 0% CPU.
> I can reproduce this, both with your location and in spearfish. And at
> first glance, it really does appear random. The only thing that I think I
> noticed, was that it happens more often when the machine is busy with
> something else. My first very wild guess would be something system
> resources, but as I said, this is very wild.
> Glynn, any hints as to where I should begin searching ?

Run v.out.ogr under gdb; when it deadlocks, hit Ctrl-C, then type
"where" to get a backtrace (assuming that this works on Windows).

Or, if you can figure out how to attach gdb to a running process,
better still, as you can also get a backtrace for the DBF driver (on
Unix, you use "attach <pid>", but I don't know if that works on

Also, "g.gisenv set=DEBUG=3" might help.

Glynn Clements <glynn at gclements.plus.com>

More information about the grass-dev mailing list