Proper way to initialize a string in C

Question

I\'ve seen people\'s code as:

char *str = NULL;

and I\'ve seen this is as well,

char *str;

I\'m wonder, what

Answer 1

Because free() doesn't do anything if you pass it a NULL value you can simplify your program like this:

char *str = NULL;

if ( somethingorother() )
{
    str = malloc ( 100 );

    if ( NULL == str )
        goto error;
}

...

error:

cleanup();
free ( str );

If for some reason somethingorother() returns 0, if you haven't initialized str you will free some random address anywhere possibly causing a failure.

I apologize for the use of goto, I know some finds it offensive. :)