CODEWITHSUNDEEP
cpointerscharacter
Salman Ahmed
Salman Ahmed

Reputation: 25

How to return a character pointer?

I'm new to C. I'm trying to return a character pointer >> A pointer that points to a single character value. I know I can simply return a character but I want to learn how to return a character pointer pointing to a single character value.

char * returnPointerToCharacter(){
    char s = 's';
    char * pointerToS = &s;
    return pointerToS;
}

int main()
{
//         This code below works  
    char h = 'h';
    char * pointerToH = &h;
    printf("%c \n", *pointerToH);

//         This code below doesn't work                
    char * pointerToS = returnPointerToCharacter();
    printf("%c \n", *pointerToS);

    return 0;
}

Upvotes: 0

Views: 65

Answers (2)

John Bollinger
John Bollinger

Reputation: 180113

I'm trying to return a character pointer

Your code does return a character pointer. But it also commits a cardinal sin: it returns a pointer to an object whose lifetime ends with the completion of the function call. The resulting pointer is therefore useless to caller.

There are several alternatives. Often, if one is going to return a pointer, one dynamically allocates the object to which it is to point. Dynamically allocated objects live until they are explicitly freed. For your particular purposes, however, I would suggest making the function's local variable static, which exactly means that it lives and retains its last-set value for the entire life of the program:

char * returnPointerToCharacter(){
    static char s = 's';

    return &s;
}

Upvotes: 0

Daniel
Daniel

Reputation: 854

The problem is that char s is on the stack, and gets popped from the stack, so you're returning a pointer to a destructed element.

If you just want a function that returns a char pointer, you could try something simple:

char * returnPointerToCharacter(char *s){
    return s;
}
...// Do stuff
char f;
char * pointerToS = returnPointerToCharacter(&f);

Upvotes: 1

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