[Gdal-dev] threads support?

[Frank Warmerdam]

On 7/30/05, William K <woklist at charter.net> wrote:
> I never really payed attention to threads vs. no threads.  I've
> always built my GDAL with threads.  I recently started looking at the
> CVS snapshots, and a few weeks ago one build worked briefly, then
> stopped working at all - gdalinfo and gdal_translate would just sit
> there idling, doing nothing (processor idle, no disk activity), but
> the ogr utilities were not affected.  It affected the libraries, so
> that GRASS would do the same (r.in.gdal, not v.in.ogr).
> 
> Reconfiguring and rebuilding, and newer snapshots, did not help.
> Happens on Mac OS 10.4 and 10.3.
> 
> Today I thought to build it without thread support, and bingo! it's
> working again.
> 
> So, did something change in the thread support in GDAL since 1.2.6?
> If I leave out thread support, how adversely would it affect other
> software, like MapServer and GRASS?

William, 

The problem is that MacOS X didn't support creating recursive 
mutexes the way I was doing it on Linux.  I have corrected this
code in port/cpl_multiproc.cpp and it works great on MacOS X now.

The aspect that changed in recent weeks is that GDAL now actually
uses the mutexes for lots of core stuff where it didn't really before. 

Best regards,
-- 
---------------------------------------+--------------------------------------
I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | Geospatial Programmer for Rent