The function size_t strlen (const char * str) calculates the length of str string (not including the ending null character).

Declare the strlen () function in C

Here is the declaration for strlen () in C:

 size_t strlen ( const char * str ) 

Parameters

str - Is a string to find the length.

Returns the value

This function returns the length of the string.

For example

The following program C illustrates the usage of strlen () in C:

 #include #include int main () { char str [ 50 ]; int len ; strcpy ( str , "Hoc C co ban va nang cao tai QTM !!!" ); len = strlen ( str ); printf ( "Do dai cua chuoi:n |%s| nla bang:n |%d|n" , str , len ); return ( 0 ); } 

Compile and run the above C program to see the results:

According to Tutorialspoint

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