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INDEX(3)
INDEX(3) FreeBSD Library Functions Manual INDEX(3)

NAME

index, rindexlocate character in string

LIBRARY

Standard C Library (libc, -lc)

SYNOPSIS

#include < strings.h>

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

char *
rindex( const char *s, int c);

DESCRIPTION

The index() and rindex() functions have been deprecated in favor of strchr(3) and strrchr(3).

The index() function locates the first occurrence of c (converted to a char) in the string pointed to by s. The terminating null character is considered part of the string; therefore if c is ‘ \0’, the functions locate the terminating ‘ \0’.

The rindex() function is identical to index(), except it locates the last occurrence of c.

RETURN VALUES

The functions index() and rindex() return a pointer to the located character, or NULL if the character does not appear in the string.

HISTORY

The index() and rindex() functions appeared in Version 6 AT&T UNIX. Their prototypes existed previously in < string.h> before they were moved to < strings.h> for IEEE Std 1003.1-2001 (“POSIX.1”) compliance. The functions are not specified by IEEE Std 1003.1-2008 (“POSIX.1”).
March 20, 2011 FreeBSD