stdlib/FreeBSD/atof.3

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  36 .\"     @(#)atof.3      8.1 (Berkeley) 6/4/93
  37 .\" $FreeBSD: src/lib/libc/stdlib/atof.3,v 1.16 2002/12/18 13:33:03 ru Exp $
  38 .\"
  39 .Dd June 4, 1993
  40 .Dt ATOF 3
  41 .Os
  42 .Sh NAME
  43 .Nm atof
  44 .Nd convert
  45 .Tn ASCII
  46 string to double
  47 .Sh LIBRARY
  48 .Lb libc
  49 .Sh SYNOPSIS
  50 .In stdlib.h
  51 .Ft double
  52 .Fn atof "const char *nptr"
  53 .Sh DESCRIPTION
  54 The
  55 .Fn atof
  56 function converts the initial portion of the string pointed to by
  57 .Fa nptr
  58 to
  59 .Vt double
  60 representation.
  61 .Pp
  62 It is equivalent to:
  63 .Bd -literal -offset indent
  64 strtod(nptr, (char **)NULL);
  65 .Ed
  66 .Pp
  67 The decimal point
  68 character is defined in the program's locale (category
  69 .Dv LC_NUMERIC ) .
  70 .Sh IMPLEMENTATION NOTES
  71 The
  72 .Fn atof
  73 function is not thread-safe and also not async-cancel-safe.
  74 .Pp
  75 The
  76 .Fn atof
  77 function has been deprecated by
  78 .Fn strtod
  79 and should not be used in new code.
  80 .Sh ERRORS
  81 The function
  82 .Fn atof
  83 need not affect the value of
  84 .Va errno
  85 on an error.
  86 .Sh SEE ALSO
  87 .Xr atoi 3 ,
  88 .Xr atol 3 ,
  89 .Xr strtod 3 ,
  90 .Xr strtol 3 ,
  91 .Xr strtoul 3
  92 .Sh STANDARDS
  93 The
  94 .Fn atof
  95 function conforms to
  96 .St -p1003.1-90 ,
  97 .St -isoC ,
  98 and
  99 .St -isoC-99 .