string/FreeBSD/index.3

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  34 .\"     @(#)index.3     8.1 (Berkeley) 6/4/93
  35 .\" $FreeBSD: src/lib/libc/string/index.3,v 1.8 2002/12/18 13:33:03 ru Exp $
  36 .\"
  37 .Dd June 4, 1993
  38 .Dt INDEX 3
  39 .Os
  40 .Sh NAME
  41 .Nm index
  42 .Nd locate character in string
  43 .Sh LIBRARY
  44 .Lb libc
  45 .Sh SYNOPSIS
  46 .In strings.h
  47 .Ft char *
  48 .Fn index "const char *s" "int c"
  49 .Sh DESCRIPTION
  50 The
  51 .Fn index
  52 function
  53 locates the first character matching
  54 .Fa c
  55 (converted to a
  56 .Vt char )
  57 in the null-terminated string
  58 .Fa s .
  59 .Sh RETURN VALUES
  60 A pointer to the character is returned if it is found; otherwise
  61 .Dv NULL
  62 is returned.
  63 If
  64 .Fa c
  65 is '\e0',
  66 .Fn index
  67 locates the terminating '\e0'.
  68 .Sh SEE ALSO
  69 .Xr memchr 3 ,
  70 .Xr rindex 3 ,
  71 .Xr strchr 3 ,
  72 .Xr strcspn 3 ,
  73 .Xr strpbrk 3 ,
  74 .Xr strrchr 3 ,
  75 .Xr strsep 3 ,
  76 .Xr strspn 3 ,
  77 .Xr strstr 3 ,
  78 .Xr strtok 3
  79 .Sh HISTORY
  80 A
  81 .Fn index
  82 function appeared in
  83 .At v6 .
  84 Its prototype existed previously in
  85 .Aq Pa string.h
  86 before it was moved to
  87 .Aq Pa strings.h
  88 for
  89 .St -p1003.1-2001
  90 compliance.