Function pointers

Could you please explain the meaning of below declaration statement.

char (*pa())[4];

Please find the entire code below.

char (*pa())[4];
void main(){
char(*p)[4]=pa();
printf("%d",**p);
}
char (*pa())[4]{
static char arr[]={'\11','\12','\13','\14'};
return &arr;
}

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[root@build ~]# cdecl
Type help' or ?' for help
cdecl> explain char (*pa())[4];
declare pa as function returning pointer to array 4 of char cdecl> explain char (*p)[4]
declare p as pointer to array 4 of char
cdecl>

Try the following code.

#include <stdio.h>

char (*pa())[4];

int main(){
        char(*p)[4]=pa();
        /*printf("%d",**p);*/
        printf("%d %d %d %d\n",(*p)[0],(*p)[1],(*p)[2],(*p)[3]);
        return 0;
}
char (*pa())[4]{
        static char arr[]={'\11','\12','\13','\14'};
        return &arr;
}

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"pa" is a function returning a pointer to an array of four characters.

C declarations work by declaring an expression involving the identifier as having a named type (in this case, "char").

"(*pa())[i]" is a character, for 0 <= i < 4.

Therefore:

"(*pa())" is an array of four characters.

Therefore:

"pa()" is a pointer to an array of four characters.

Therefore:

"pa" is a function returning a pointer to an array of four characters.

Glynn Clements <[email protected]>

You already have got the required answer from others.
C and function pointers can always be confusing. At times you think you have understood it throughly and but still not be able to decode some more complex declarations. (cdec can come to help but not always..at least not in a technical interview ) The best approach that I have come across is the Clockwise Spiral rule. (link :
http://www.c-faq.com/decl/spiral.anderson.html )

Hope this helps..

Thanks & Regards
Milind A Choudhary
http://www.csl.mtu.edu/~machoudh/

Milind  Arun Choudhary

Wrong.

1. pa is not a pointer to a function, it's a function which returns a pointer. "()" has higher precedence than "*", so "*pa()" is parsed as "*(pa())" (function returning pointer) rather than "(*pa)()" (pointer to function).

2. An empty parameter list "()" indicates that the function takes unspecified arguments. A function which takes no arguments has "(void)" as the parameter list.

Glynn Clements <[email protected]>