Linking Libraries using f2py

Question

I have a fortran program that uses some library files. I am trying to link them along with the module file being created.

The library file I am trying to link is called ulib.a and is located in the directory /home/replace/lib/

The command I am using is:

f2py -L/home/replace/lib/ -lulib.a -c main.f -m progs

I am getting the following error:

/usr/bin/ld: cannot find -lulib.a
collect2: ld returned 1 exit status
/usr/bin/ld: cannot find -lulib.a
collect2: ld returned 1 exit status

I would appreciate any help!

Answer 1

Try leaving off the .a - I am reasonably sure that the linker already knows that libraries are .a so in your example it will be looking for ulib.a.a and failing.

Answer 2

I had to remove the extension from the library name and also provide the full path. For some reason providing the path using the -L argument did not work.

f2py -l/home/replace/lib/ulib -c main.f -m progs

Answer 3

The library should have the full name libxxx.a where xxx is the given name. Then do

f2py -L. -lxxx -c main.f90 -m progs

Note that only xxx comes after -l. If you create the library yourself remember to include -fPIC. For example, it could look like this:

gfortran -c -fPIC source1.f90 source2.f90
ar crs libxxx.a obj1.o obj2.o
f2py -L. -lxxx -c main.f90 -m progs

Found guidance in this example: https://modelingguru.nasa.gov/docs/DOC-2343