strlen -- Compute Length of Null-Terminated String


SYNOPSIS
#include <string.h>
size_t strlen(const char *str);
DESCRIPTION
strlen
returns the length of a null-terminated character string
str
.
RETURN VALUE
The return value is the length of the string, not counting the
terminating null.
CAUTION
The scan for a null character continues until one is found, or until a
protection or addressing exception occurs.
PORTABILITY
Note that many implementations before ANSI C define strlen
to return
int
rather than size_t
.
IMPLEMENTATION
If <string.h>
is included (by an #include
statement) and strlen
is not undefined (by an #undef
statement), strlen
generates inline code. If the argument to
strlen
is a constant, the length is evaluated during compilation,
and no code is generated for the function.
EXAMPLE
#include <string.h>
#include <stdio.h>
#define MAXLINE 100
main()
{
char line[MAXLINE+1];
puts("Enter some text (at least 2 characters):");
gets(line);
puts("The last half of your text is:");
puts(line + (strlen(line)/2));
}
RELATED FUNCTIONS
mblen
SEE ALSO
String Utility Functions