C : How to read that definition ....

[DonJoky]

Hello all,

I'd like to ask you to help me to understand this definition in "C"

int (*f (float (*) (long), char *)) (double);

How can I read this definition?
How can I call this function?

It's example from C programming, a modern approach (K.N.King)

Thank you very much.
Have a nice day.
Best regards,

Jozef

 

[DutchDaemon]

Why not just ask at a programming or C forum? Are you using FreeBSD?

 

[DonJoky]

Hello @DutchDaemon,

Yes, I'm using FreeBSD 9.1-RELEASE. I'm studying the C language. I thought, I can put that question here, sorry.

Jozef

 

[DutchDaemon]

You can, but this is not really a forum where a lot of programmers hang out and share their experiences. So a dedicated programming forum might work better/faster.

 

[wblock@]

It's example from C programming, a modern approach (K.N.King)

What page?

 

[DonJoky]

Chapter 18, page 481, Excercise 12

 

[tmw]

Hello,

signal(3)

The signal function might give you some clue how to interpret your function

 

[throAU]

The way to read that is to find out who wrote the code, and get them to fix it or be shot.

 

[DonJoky]

Hi all,

Yesterday I found a great article about that issue.
c-faq.com/decl/spiral.anderson.html
Now I understand it, it's clear and easy
Thank you to all.
Have a nice day.

Jozef

 

[expl]

Function pointers are quite ugly. I'd recommend not to use definitions like this directly in your code, instead wrap them in typedefs and put a comment above for yourself/others, describing the function it points to.

 

[fluca1978]

int (*f ([color="Red"]float (*) (long)[/color], char *)) (double);

Ok, but was the above correct?

 

[tmw]

It is.
Keep in mind that this is a prototype.

 

[expl]

Ok, but was the above correct?

The red part means argument that is a pointer to a function that returns float and takes a single long.