#3 missing argument

[grumpf_]

cc -Wall -g -I ../include -c srv.c
srv.c: In function ‘sp_srv_create’:
srv.c:73: warning: assignment from incompatible pointer type

from spfs.h
...
Spfcall (attach)(Spfid fid, Spfid afid, Spstr uname,
Spstr aname, u32 n_uname);

...
srv.c
Spfcall sp_default_attach(Spfid fid, Spfid afid, Spstr uname, Spstr *aname);

you are missing one argument