How should I use array of function pointers in C?
How can I initialize them?
This question has been already answered with very good examples. The only example that might be missing is one where the functions return pointers. I wrote another example with this, and added lots of comments, in case someone finds it helpful:
#include
char * func1(char *a) {
*a = 'b';
return a;
}
char * func2(char *a) {
*a = 'c';
return a;
}
int main() {
char a = 'a';
/* declare array of function pointers
* the function pointer types are char * name(char *)
* A pointer to this type of function would be just
* put * before name, and parenthesis around *name:
* char * (*name)(char *)
* An array of these pointers is the same with [x]
*/
char * (*functions[2])(char *) = {func1, func2};
printf("%c, ", a);
/* the functions return a pointer, so I need to deference pointer
* Thats why the * in front of the parenthesis (in case it confused you)
*/
printf("%c, ", *(*functions[0])(&a));
printf("%c\n", *(*functions[1])(&a));
a = 'a';
/* creating 'name' for a function pointer type
* funcp is equivalent to type char *(*funcname)(char *)
*/
typedef char *(*funcp)(char *);
/* Now the declaration of the array of function pointers
* becomes easier
*/
funcp functions2[2] = {func1, func2};
printf("%c, ", a);
printf("%c, ", *(*functions2[0])(&a));
printf("%c\n", *(*functions2[1])(&a));
return 0;
}