strchr(3) Library Functions Manual strchr(3)

strchr, strrchr, strchrnul - locate character in string

Standard C library (libc, -lc)

#include <string.h>
char *strchr(const char *s, int c);
char *strrchr(const char *s, int c);
#define _GNU_SOURCE         /* See feature_test_macros(7) */
#include <string.h>
char *strchrnul(const char *s, int c);

The strchr() function returns a pointer to the first occurrence of the character c in the string s.

The strrchr() function returns a pointer to the last occurrence of the character c in the string s.

The strchrnul() function is like strchr() except that if c is not found in s, then it returns a pointer to the null byte at the end of s, rather than NULL.

Here "character" means "byte"; these functions do not work with wide or multibyte characters.

The strchr() and strrchr() functions return a pointer to the matched character or NULL if the character is not found. The terminating null byte is considered part of the string, so that if c is specified as '\0', these functions return a pointer to the terminator.

The strchrnul() function returns a pointer to the matched character, or a pointer to the null byte at the end of s (i.e., s+strlen(s)) if the character is not found.

For an explanation of the terms used in this section, see attributes(7).

Interface Attribute Value
strchr (), strrchr (), strchrnul () Thread safety MT-Safe

C11, POSIX.1-2008.
GNU.

POSIX.1-2001, C89, SVr4, 4.3BSD.
glibc 2.1.1, FreeBSD 10, NetBSD 8.

memchr(3), string(3), strlen(3), strpbrk(3), strsep(3), strspn(3), strstr(3), strtok(3), wcschr(3), wcsrchr(3)

2024-05-02 Linux man-pages 6.8