Transfers control and passes arguments to a function. Format:
nam (p[,p]...)
nam Is the name of the function or the name of an entry
point to the function.
p Is a value to be passed to the function. The value
can be a constant, the name of a variable, the name
of an array element, the name of an array, an expression,
a substring, field reference, or the name of a subprogram
or entry point to a subprogram (must be defined as
external). You cannot specify more than 255 arguments.