Get the next overloaded version of a procedure or function.

A procedure or function reference or NULL if no overloading subroutine is defined.

This function returns the following overloading defined for the given subroutine. A subroutine may be defined several times in a model with different sets of parameters. This function gives access to all the defined overloaded versions of a subroutine.

XPRMgetprocinfo.