the null character

[masiht]

I am reading the character sequences section of this tutorial here.
It has mentioned the null character '0' but it doesn't have any example.
please give me a simple example of null character.

[Bazzy]

The null character '\0' is used to terminate C strings

eg: char hello[6] = "Hello"; is the same as char hello[6] = { 'H', 'e', 'l', 'l', 'o', '\0' };

if you try this code:

cout << "hello\0world";

It will show only "hello" as when a null character is found the string is terminated


'\0' has the same value as char( 0 )

[masiht]

eg: char hello[6] = "Hello"; is the same as char hello[6] = { 'H', 'e', 'l', 'l', 'o', '\0' };

why did we put null character in this code because we can put less then the arrays element.

[Bazzy]

Using "Hello" the null character is automatically added, using { 'H', 'e', 'l', 'l', 'o', '\0' } you have to put it or when diplaying the array you will see all characters until the next '\0'

eg:

char hello[]={'H','e','l','l','o'};
cout << hello;

Result:

HelloÌÌÌÌÌÌÌÌÌÌÌ

Other example:

char hello[]={'H','e','l','l','o'};
char world[] = {'W','o','r','l','d'};
cout << world;

Result:

WorldÌÌÌÌÌÌÌÌÌÌÌHelloÌÌÌÌÌÌÌÌÌÌÌ

hello was stored in memory just a few bytes after world and both of them are shown as there aren't null characters between them

[Duthomhas]

Please be aware that Bazzy's example is OS- and compiler-dependant. YRMV.

[Bazzy]

That was just to show that without '\0' you get strange result, often with the same compiler and OS I get different outputs when I forget a '\0'

[masiht]

does it mean that we have to use null character always with an array as it gives strange result without null character?

[helios]

Only when those arrays are initialized with the syntax Bazzy used above:
char hello[]={'H','e','l','l','o','\0'};
You don't have to if you use this syntax:

char *hello="Hello";
//or
char hello[]="Hello";

[Bazzy]

Everything with double quotes already have a null character at the end