CODEWITHSUNDEEP
cpointersstructchar
Jack Murrow
Jack Murrow

Reputation: 426

Is it ok to assign uninitialized char pointer or char pointer in struct?

struct Test {
    char *s;
};

Test test;
test.s = "Hey";

or

char *s;

s = "Hey";

So I don't need the string to be edited, or anything like that. I was just wondering if the code above me is allowed, or is safe to use?

And if this should not be used, why?

Or, if there is a better way I should do this?

Upvotes: 1

Views: 442

Answers (1)

ikegami
ikegami

Reputation: 386461

It is allowed. You won't even get a warning from -Wall or -Wextra, though you will with -Wwrite-strings.

It is safe as long as you don't change any of the elements of the array to which s points (e.g. *s or s[0]) or try to free s.

You'll probably run into problems if you deal with a bunch of Test and some strings are read-only and some aren't. For example, how would you know if a string should be freed when the Test is destroyed?

If none of your strings will be edited or freed, you could use the following to get at least a warning if you try to do something you shouldn't:

struct Test {
    const char *s;
};

In the other direction, you could make a copy of the string that can be edited and/or freed.

test.s = strdup("Hey");

Upvotes: 1

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