Initialize a string in C to empty string

Question

I want to initialize string in C to empty string. I tried:

string[0] = \"\"; 

but it wrote

\"warning: assignment makes inte         


        

Answer 1

string[0] = "";

"warning: assignment makes integer from pointer without a cast

Ok, let's dive into the expression ...

0 an int: represents the number of chars (assuming string is (or decayed into) a char*) to advance from the beginning of the object string

string[0]: the char object located at the beginning of the object string

"": string literal: an object of type char[1]

=: assignment operator: tries to assign a value of type char[1] to an object of type char. char[1] (decayed to char*) and char are not assignment compatible, but the compiler trusts you (the programmer) and goes ahead with the assignment anyway by casting the type char* (what char[1] decayed to) to an int --- and you get the warning as a bonus. You have a really nice compiler :-)

Answer 2

In addition to Will Dean's version, the following are common for whole buffer initialization:

char s[10] = {'\0'};

or

char s[10];
memset(s, '\0', sizeof(s));

or

char s[10];
strncpy(s, "", sizeof(s));

Answer 3

I think Amarghosh answered correctly. If you want to Initialize an empty string(without knowing the size) the best way is:

//this will create an empty string without no memory allocation. 
char str[]="";// it is look like {0}

But if you want initialize a string with a fixed memory allocation you can do:

// this is better if you know your string size.    
char str[5]=""; // it is look like {0, 0, 0, 0, 0}