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strchr

Section: C Library Functions (3)
Updated: 202-0-08
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NAME

strchr, strrchr, strchrnul - locate character in string

LIBRARY

Standard C library (libc,~-lc)

SYNOPSIS

#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);

DESCRIPTION

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.

RETURN VALUE

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 [aq][rs]0[aq], 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.

ATTRIBUTES

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

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

STANDARDS

strchr(): strrchr() C11, POSIX.-2008.
strchrnul(): GNU.

HISTORY

strchr(): strrchr() POSIX.-2001, C89, SVr4, 4.3BSD.
strchrnul(): glibc 2.1.1, FreeBSD 10, NetBSD 8.