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authorDavid Schultz <das@FreeBSD.org>2003-03-12 20:31:05 +0000
committerDavid Schultz <das@FreeBSD.org>2003-03-12 20:31:05 +0000
commit703d65601d610ae7528bb67fed551a3e0cd41e90 (patch)
tree32f11cbd737d895e4ac5f30eca7870febbb096d3
parent6a66acb565dde6d5b0ee52eef2a631fbb09df153 (diff)
downloadsrc-test2-703d65601d610ae7528bb67fed551a3e0cd41e90.tar.gz
src-test2-703d65601d610ae7528bb67fed551a3e0cd41e90.zip
Notes
-rw-r--r--lib/libc/stdlib/strtod.3107
1 files changed, 75 insertions, 32 deletions
diff --git a/lib/libc/stdlib/strtod.3 b/lib/libc/stdlib/strtod.3
index ab78083ca5e7..b7b8f377add7 100644
--- a/lib/libc/stdlib/strtod.3
+++ b/lib/libc/stdlib/strtod.3
@@ -36,37 +36,65 @@
.\" @(#)strtod.3 8.1 (Berkeley) 6/4/93
.\" $FreeBSD$
.\"
-.Dd June 4, 1993
+.Dd March 2, 2003
.Dt STRTOD 3
.Os
.Sh NAME
-.Nm strtod
+.Nm strtod , strtof , strtold
.Nd convert
.Tn ASCII
-string to double
+string to floating point
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In stdlib.h
.Ft double
.Fn strtod "const char * restrict nptr" "char ** restrict endptr"
+.Ft float
+.Fn strtof "const char * restrict nptr" "char ** restrict endptr"
+.Ft long double
+.Fn strtold "const char * restrict nptr" "char ** restrict endptr"
.Sh DESCRIPTION
-The
-.Fn strtod
-function converts the initial portion of the string
+These conversion
+functions convert the initial portion of the string
pointed to by
.Fa nptr
to
-.Vt double
-representation.
+.Vt double ,
+.Vt float ,
+and
+.Vt long double
+representation, respectively.
.Pp
The expected form of the string is an optional plus (``+'') or minus
-sign (``\-'') followed by a sequence of digits optionally containing
-a decimal-point character, optionally followed by an exponent.
-An exponent consists of an ``E'' or ``e'', followed by an optional plus
-or minus sign, followed by a sequence of digits.
+sign (``\-'') followed by either:
+.Bl -bullet
+.It
+a decimal significand consisting of a sequence of decimal digits
+optionally containing a decimal-point character, or
+.It
+a hexadecimal significand consisting of a ``0X'' or ``0x'' followed
+by a sequence of hexadecimal digits optionally containing a
+decimal-point character.
+.El
+.Pp
+In both cases, the significand may be optionally followed by an
+exponent.
+An exponent consists of an ``E'' or ``e'' (for decimal
+constants) or a ``P'' or ``p'' (for hexadecimal constants),
+followed by an optional plus or minus sign, followed by a
+sequence of decimal digits.
+For decimal constants, the exponent indicates the power of 10 by
+which the significand should be scaled.
+For hexadecimal constants, the scaling is instead done by powers
+of 2.
.Pp
-Leading white-space characters in the string (as defined by the
+Alternatively, if the portion of the string following the optional
+plus or minus sign begins with ``INFINITY'' or ``NAN'', ignoring
+case, it is interpreted as an infinity or a quiet NaN, respectively.
+.Pp
+In any of the above cases, leading white-space characters in the
+string (as defined by the
.Xr isspace 3
function) are skipped.
The decimal point
@@ -74,8 +102,11 @@ character is defined in the program's locale (category
.Dv LC_NUMERIC ) .
.Sh RETURN VALUES
The
-.Fn strtod
-function returns the converted value, if any.
+.Fn strtod ,
+.Fn strtof ,
+and
+.Fn strtold
+functions return the converted value, if any.
.Pp
If
.Fa endptr
@@ -91,8 +122,11 @@ is stored in the location referenced by
.Fa endptr .
.Pp
If the correct value would cause overflow, plus or minus
-.Dv HUGE_VAL
-is returned (according to the sign of the value), and
+.Dv HUGE_VAL ,
+.Dv HUGE_VALF ,
+or
+.Dv HUGE_VALL
+is returned (according to the sign and type of the return value), and
.Er ERANGE
is stored in
.Va errno .
@@ -118,24 +152,33 @@ The
.Fn strtod
function
conforms to
-.St -isoC .
+.St -isoC-99 ,
+with the exception of the bug noted below.
+.Sh BUGS
+These routines do not recognize the C99 ``NaN(...)'' syntax.
.Sh AUTHORS
The author of this software is
.An David M. Gay .
.Pp
-Copyright (c) 1991 by AT&T.
+Copyright (c) 1998 by Lucent Technologies
+.br
+All Rights Reserved
.Pp
-Permission to use, copy, modify, and distribute this software for any
-purpose without fee is hereby granted, provided that this entire notice
-is included in all copies of any software which is or includes a copy
-or modification of this software and in all copies of the supporting
-documentation for such software.
+Permission to use, copy, modify, and distribute this software and
+its documentation for any purpose and without fee is hereby
+granted, provided that the above copyright notice appear in all
+copies and that both that the copyright notice and this
+permission notice and warranty disclaimer appear in supporting
+documentation, and that the name of Lucent or any of its entities
+not be used in advertising or publicity pertaining to
+distribution of the software without specific, written prior
+permission.
.Pp
-THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
-WARRANTY. IN PARTICULAR, NEITHER THE AUTHOR NOR AT&T MAKES ANY
-REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY
-OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
-.Pp
-Contact your vendor for a free copy of the source code to
-.Fn strtod
-and accompanying functions.
+LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
+IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
+SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
+IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
+ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
+THIS SOFTWARE.