Dear Manuele, For ctypes in pygrass, the C-libraries need to be loaded explicitly.
You could have a look here: https://github.com/zarch/grass-session/blob/6097f834be20ee0d703deb2af90f22d6dc66f368/grass_session/session.py#L332 to see how it can be done, or just use the grass_session python library (pip install grass-session) for convenience… Cheers Stefan From: grass-user <[email protected]> On Behalf Of Manuele Pesenti Sent: fredag 20. august 2021 16:40 To: grass-user <[email protected]> Subject: [GRASS-user] Error import from grass.pygrass.vector library Dear All, I'm moving my first steps on the development of a python script that uses Grass, but I cannot import from the grass.pygrass.vector library. I work on a Ubuntu/Linux environment and I've installed grass using apt, this is the test script I'm currently running: # -*- coding: utf-8 -*- import os, sys GISBASE = '/usr/lib/grass78' GRASSBIN = '/usr/bin/grass78' # Define GRASS-Python environment os.environ['GISBASE'] = GISBASE os.environ['GRASSBIN'] = GRASSBIN sys.path.append(os.path.join(GISBASE, "etc", "python")) from grass_session import Session import grass.script as gs print(f"LD_LIBRARY_PATH: {os.environ['LD_LIBRARY_PATH']}") print(f"GRASSBIN: {os.environ['GRASSBIN']}") from grass.pygrass.vector import Vector print('DONE!') and this is the output: $ python import_test.py LD_LIBRARY_PATH: /usr/lib/grass78/lib GRASSBIN: /usr/bin/grass78 Traceback (most recent call last): File "/usr/lib/grass78/etc/python/grass/lib/ctypes_loader.py", line 76, in load return ctypes.cdll.LoadLibrary(path) File "/usr/lib/python3.9/ctypes/__init__.py", line 452, in LoadLibrary return self._dlltype(name) File "/usr/lib/python3.9/ctypes/__init__.py", line 374, in __init__ self._handle = _dlopen(self._name, mode) OSError: libgrass_datetime.7.8.so: cannot open shared object file: No such file or directory During handling of the above exception, another exception occurred: Traceback (most recent call last): File "/home/manuele/Lavoro/ETS/ETSCore/scripts/import_test.py", line 21, in <module> from grass.pygrass.vector import Vector File "/usr/lib/grass78/etc/python/grass/pygrass/vector/__init__.py", line 5, in <module> import grass.lib.gis as libgis File "/usr/lib/grass78/etc/python/grass/lib/gis.py", line 23, in <module> _libs["grass_gis.7.8"] = load_library("grass_gis.7.8") File "/usr/lib/grass78/etc/python/grass/lib/ctypes_loader.py", line 62, in load_library return self.load(path) File "/usr/lib/grass78/etc/python/grass/lib/ctypes_loader.py", line 78, in load raise ImportError(e) ImportError: libgrass_datetime.7.8.so: cannot open shared object file: No such file or directory Thank you very mutch for any help Cheers Manuele
_______________________________________________ grass-user mailing list [email protected] https://lists.osgeo.org/mailman/listinfo/grass-user
