How to use strlen in c language

The strlen function is used to obtain the length of a string, that is, the number of valid characters in the string: Syntax: size_t strlen(const char *str); Parameters: str: The string whose length is to be calculated, starting with 0 Ending character pointer; return value: Returns the number of characters in the string str, excluding the 0-terminating character.

Strlen function in C language

Purpose:
Strlen function is used Used to get the length of a string, that is, the number of valid characters in the string.

Syntax:

<code class="c">size_t strlen(const char *str);</code>

Parameters:

• str: To calculate the length String, 0-terminated character pointer.

Return value:
Returns the number of characters in the string str, excluding the 0-terminating character.

Usage:

1. Declare a character array or string, for example:

   <code class="c">char str[] = "Hello World";</code>

2. Use The strlen function calculates the string length, for example:

   <code class="c">size_t len = strlen(str);</code>

Example:

<code class="c">#include <stdio.h>
#include <string.h>

int main() {
    char str[] = "C Language";
    size_t len = strlen(str);

    printf("String: %s\n", str);
    printf("Length: %zu\n", len);

    return 0;
}</code>

Output:

<code>String: C Language
Length: 10</code>

Note:

• strlen function does not count 0-terminating characters.
• The string must be terminated with 0, otherwise the function will return unpredictable results.
• The strlen function does not modify the content of the string.
• For an empty string, the strlen function returns 0.

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