> Marc had the right idea: a configure test is the only real way to
> discover how getsockname() is declared. A small problem is that
> configure can only detect outright compilation failures, not warnings.
> That's probably good enough, but people with nonstandard definitions
> of getsockname may have to live with looking at warnings.
Just redeclare the function with the parameters you expect. Most compilers
will fail if you redeclare with parameters of different types or different
number of parameters, but silently ignore functionally identical prototype
lines.
Taral