STRCHR(3) | Library Functions Manual | STRCHR(3)

# NAME

`strchr`, `index` — locate first occurrence of a character in a string

# SYNOPSIS

`#include <string.h>`

char *
`strchr`(const char *s, int c);

`#include <strings.h>`

char *
`index`(const char *s, int c);

# DESCRIPTION

The `strchr`() function locates the first occurrence of the character c (converted to a char) in the string s. The terminating NUL character is considered part of the string. If c is ‘`\0`’, `strchr`() locates the terminating ‘`\0`’.

The `index`() function is an old synonym for `strchr`().

# RETURN VALUES

The `strchr`() function returns a pointer to the located character or `NULL` if the character does not appear in the string.

# EXAMPLES

After the following call to `strchr`(), p will point to the string "oobar":

    char *p;
    char *s = "foobar";

    p = strchr(s, 'o');

# SEE ALSO

memchr(3), strcspn(3), strpbrk(3), strrchr(3), strsep(3), strspn(3), strstr(3), strtok(3), wcschr(3)

# STANDARDS

The `strchr`() function conforms to ANSI X3.159-1989 (“ANSI C89”).

The `index`() function is deprecated and shouldn't be used in new code.

# HISTORY

The `index`() function first appeared in Version 7 AT&T UNIX. The `strchr`() function first appeared in AT&T System III UNIX and was reimplemented for 4.3BSD.

December 11, 2024 | Debian