blp:~(0)$ cdecl
Type `help' or `?' for help
cdecl> declare function returning pointer to function returning int;
int (*f())()
cdecl>

Hi,

I've come across a problem trying to define a function that returns a
pointer to another function type (without using typedefs :).

I've come up with the following which I thought would have been right,
but it's not!

int (*)(int) func(void)
{
    ...

Here, func should return a pointer to a function taking an int as
a parameter and returning an int. Is there any way to do this, or
do you have to use typedefs?

furos

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ah, a {*filter*}  :-)

Try:-
    int (*func (void)) (int);
It gave me a headache.

Isn't this easier:-
  typedef int (*Ifunc) (int);
  typedef Ifunc (*Ffunc) (void);
  Ffunc func;

IMHO the only reason to know the first way is work out what someone is
trying to do then you can replace it with something human beings can
understand.

Take a look at the definition of signal() if you *really* want to hurt
your mind...

--

It isn't a program, it's a 1000 patches flying in
loose formation.

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Before you buy.

Take it one step at a time.  For these kinds of problems, I work from
the outside in.

1.  int f (int x)  -- f is a function taking one int parameter
                      and returning an int
2.  f = (*g)       -- g is a pointer.  Substitute for f in (1) to get
                      int (*g)(int x).  g is a pointer to a function
                      taking one int parameter and returning an int.
3.  g = h(void)    -- h is a function.  Substitute for g in (2) to get
                      int (*h(void))(int x).  h is a function which
                      takes no parameters and returns a pointer to a
                      function which takes one int parameter and
                      returns int.

Hope the derivation makes sense.  It's a lot easier on everyone to just
use typedefs, though.

--
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                     | High Technology Problems

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