Pointers to functions

[Greg Comeau]

In article <AJ3U.91May14140642 at wilbury.cs.virginia.edu> aj3u at wilbury.cs.virginia.edu (Asim Jalis) writes:
>pf = hello;	and     pf = &hello;
>The definitions for pf and hello are as follows:
>void (*pf)();	// pointer to a function
>void hello() {   printf("Hello World\n"); }
>I used the two different forms of assignments and got the same output.
>Is there a difference between them?

There is a difference even though they both end up at the same.

In 'pf = hello;', the function name expression is implicitly converted into
a pointer to a function of the appropriate type (a void(*)()) when in this
context.

With 'pf = &hello;', since the operand of & is a function, it is a pointer
to a function of the appropriate type.  It does not become a pointer to a
pointer to a function.

The C++ style is to use the & form.

- Greg
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