function pointer and pointer to function

[prashant.khade1623@gmail.com]

Hi all,

Are function pointer and pointer to a function same ?

How do we declare a function pointer ?

How to declare an array of function pointers ?

Can you please give some examples for these.

Thanks,

[Philip Potter]

Re: function pointer and pointer to function

prashant.khade1 623@gmail.com wrote:

Hi all,
>
Are function pointer and pointer to a function same ?

Yes.

How do we declare a function pointer ?

It depends on the type of function you want to point to. For example, to
declare fp as a pointer to a function taking char * and returning int,
you'd say:

int (*fp)(char *);

All parenthesis () are necessary. If you say:

int *fp(char *);

then you're declaring fp as a function taking 'char *' and returning
'int *'.

How to declare an array of function pointers ?

When things get more complicated, such as arrays of function pointers,
or pointers to functions taking pointers to functions and returning a
pointer to function, you can still declare them directly, but you can
also do it in stages using typedefs. There's a wonderful example in the
FAQ, question 1.21.

Philip

[prashant.khade1623@gmail.com]

Re: function pointer and pointer to function

On Apr 10, 4:17 pm, Philip Potter <p...@doc.ic.ac .ukwrote:

prashant.khade1 ...@gmail.com wrote:

Hi all,

>

Are function pointer and pointer to a function same ?

>
Yes.
>

How do we declare a function pointer ?

>
It depends on the type of function you want to point to. For example, to
declare fp as a pointer to a function taking char * and returning int,
you'd say:
>
int (*fp)(char *);
>
All parenthesis () are necessary. If you say:
>
int *fp(char *);
>
then you're declaring fp as a function taking 'char *' and returning
'int *'.
>

How to declare an array of function pointers ?

>
When things get more complicated, such as arrays of function pointers,
or pointers to functions taking pointers to functions and returning a
pointer to function, you can still declare them directly, but you can
also do it in stages using typedefs. There's a wonderful example in the
FAQ, question 1.21.
>
Philip

thanks for your help...

I need to know about declaring array of function pointers and how to
use them

[Philip Potter]

Re: function pointer and pointer to function

prashant.khade1 623@gmail.com wrote:

On Apr 10, 4:17 pm, Philip Potter <p...@doc.ic.ac .ukwrote:

>prashant.khade 1...@gmail.com wrote:

>>How to declare an array of function pointers ?

>When things get more complicated, such as arrays of function pointers,
>or pointers to functions taking pointers to functions and returning a
>pointer to function, you can still declare them directly, but you can
>also do it in stages using typedefs. There's a wonderful example in the
>FAQ, question 1.21.
>>
>Philip

>
thanks for your help...
>
I need to know about declaring array of function pointers and how to
use them

I have already answered your question. I have quoted my answer above. If
you still don't understand, ask more specific questions - if you ask the
same question again, I can't tell which bit of my answer you haven't
understood.

[Peter 'Shaggy' Haywood]

Re: function pointer and pointer to function

Groovy hepcat Philip Potter was jivin' in comp.lang.c on Fri, 11 Apr
2008 5:30 pm. It's a cool scene! Dig it.

prashant.khade1 623@gmail.com wrote:

>On Apr 10, 4:17 pm, Philip Potter <p...@doc.ic.ac .ukwrote:

>>prashant.khad e1...@gmail.com wrote:
>>>How to declare an array of function pointers ?
>>When things get more complicated, such as arrays of function
>>pointers, or pointers to functions taking pointers to functions and
>>returning a pointer to function, you can still declare them
>>directly, but you can also do it in stages using typedefs. There's a
>>wonderful example in the FAQ, question 1.21.
>>>
>>Philip

>>
>thanks for your help...
>>
>I need to know about declaring array of function pointers and how to
>use them

>
I have already answered your question. I have quoted my answer above.
If you still don't understand, ask more specific questions - if you
ask the same question again, I can't tell which bit of my answer you
haven't understood.

True the OP *could* declare an array of pointer to function by using
typedef, but I think he wants to declare it directly. It's easy enough.
You haven't forgotten how to do it, have you, Phil? :)

int (*fpa[10])(int);

This declares an array of 10 pointers to function taking and int and
returning an int.

--
Dig the sig!

----------- Peter 'Shaggy' Haywood ------------
Ain't I'm a dawg!!