C - Complicated pointer declarations - help understanding

Posted by Emmel on Stack Overflow See other posts from Stack Overflow or by Emmel
Published on 2010-04-18T18:05:29Z Indexed on 2010/04/18 18:13 UTC
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In my burgeoning new self-education in the C language, I've come across a set of declarations that I do not understand how to read. I'd love for someone to break these down. I'll explain at the bottom where I got these examples from.

1.

char (*(*x())[])()

"x: function returning pointer to array[] of pointer to function returning char" - huh?

2.

char (*(*x[3])())[5]

"x: array[3] of pointer to function returning pointer to array[5] of char" - come again?

3.

 char **argv

This I understand. "Pointer to pointer to char." But what I don't understand is -- what's the use case for a pointer to a pointer?

Follow-up question: does anyone every use declarations this complex or is this just academic fun on the part of the authors of the examples I got this from?

These examples are from section 5.12 of the K&R book. This is the first time I'm genuinely stumped by an explanation, in an otherwise well-written classic.

Thanks.

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C - Complicated pointer declarations - help understanding - Developer IT

C - Complicated pointer declarations - help understanding

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