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C string strlen() function

❮ string Functions


Example

Measure the length of a string:

char myStr[20] = "Hello World";
printf("%zu\n", strlen(myStr));
printf("%zu\n", sizeof(myStr));
Try it Yourself »

Definition and Usage

The strlen() function returns the length of a string, which is the number of characters up to the first null terminating character. This is smaller than the amount of memory that is reserved for the string, which can be measured using the sizeof operator instead.

The strlen() function is defined in the <string.h> header file.


Syntax

strlen(char * str);

Parameter Values

Parameter Description
str Required. A string to measure the length of.

Technical Details

Returns: An integer representing the length of the string.

❮ string Functions


Related Pages

C Strings Tutorial

C String Functions Tutorial


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