string/FreeBSD/strlen.3

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  32 .\"     @(#)strlen.3    8.1 (Berkeley) 6/4/93
  33 .\" $FreeBSD: src/lib/libc/string/strlen.3,v 1.9 2009/04/07 13:42:53 trasz Exp $
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  35 .Dd February 28, 2009
  36 .Dt STRLEN 3
  37 .Os
  38 .Sh NAME
  39 .Nm strlen, strnlen
  40 .Nd find length of string
  41 .Sh LIBRARY
  42 .Lb libc
  43 .Sh SYNOPSIS
  44 .In string.h
  45 .Ft size_t
  46 .Fn strlen "const char *s"
  47 .Ft size_t
  48 .Fn strnlen "const char *s" "size_t maxlen"
  49 .Sh DESCRIPTION
  50 The
  51 .Fn strlen
  52 function
  53 computes the length of the string
  54 .Fa s .
  55 The
  56 .Fn strnlen
  57 function attempts to compute the length of
  58 .Fa s ,
  59 but never scans beyond the first
  60 .Fa maxlen
  61 bytes of
  62 .Fa s .
  63 .Sh RETURN VALUES
  64 The
  65 .Fn strlen
  66 function
  67 returns
  68 the number of characters that precede the
  69 terminating
  70 .Dv NUL
  71 character.
  72 The
  73 .Fn strnlen
  74 function returns either the same result as
  75 .Fn strlen
  76 or
  77 .Fa maxlen ,
  78 whichever is smaller.
  79 .Sh SEE ALSO
  80 .Xr string 3 ,
  81 .Xr wcslen 3 ,
  82 .Xr wcswidth 3
  83 .Sh STANDARDS
  84 The
  85 .Fn strlen
  86 function
  87 conforms to
  88 .St -isoC .
  89 The
  90 .Fn strnlen
  91 function conforms to
  92 .St -p1003.1-2008 .