Question

Suppose I have functions:

void func1(int x)
{
    ....
}

void func2(int x, int y)
{
    ....
}

void func3(int x, int y, int z)
{
    ....
}

And say that I want to have a function pointer within a struct:

For example

typedef struct{
     char *ename;
     char **pname;
    < and here I want to have a function pointer> ??
} Example;

Example ex[3];

Now, I want to populate the ex[3] array as:

ex[0].ename = "X0";
ex[0].pname[0]="A0";
ex[0].pname[1]="B0";
ex[0].<function pointer to func1() > ??


ex[1].ename = "X1";
ex[1].pname[0]="A1";
ex[1].pname[1]="B1";
ex[1].<function pointer to func2() > ??

… and so on…

Is it possible to create something like this? Please help me with this. Thanks.

Answer 1

I would use a union of function pointers:

union {
    void (*fun1)(int);
    void (*fun2)(int, int);
} fptr;

You also need a field in the struct to tell which is used.