Plan 9 from Bell Labs’s /usr/web/sources/contrib/fgb/root/sys/lib/ape/man/3/wcstol

Copyright © 2021 Plan 9 Foundation.
Distributed under the MIT License.
Download the Plan 9 distribution.


.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved 
.TH "WCSTOL" 3P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual"
.\" wcstol 
.SH PROLOG
This manual page is part of the POSIX Programmer's Manual.
The Linux implementation of this interface may differ (consult
the corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
.SH NAME
wcstol, wcstoll \- convert a wide-character string to a long integer
.SH SYNOPSIS
.LP
\fB#include <wchar.h>
.br
.sp
long wcstol(const wchar_t *restrict\fP \fInptr\fP\fB, wchar_t **restrict\fP
\fIendptr\fP\fB,
.br
\ \ \ \ \ \  int\fP \fIbase\fP\fB);
.br
long long wcstoll(const wchar_t *restrict\fP \fInptr\fP\fB,
.br
\ \ \ \ \ \  wchar_t **restrict\fP \fIendptr\fP\fB, int\fP \fIbase\fP\fB);
.br
\fP
.SH DESCRIPTION
.LP
These functions shall convert the initial portion of the wide-character
string pointed to by \fInptr\fP to \fBlong\fP, \fBlong
long\fP, \fBunsigned long\fP, and \fBunsigned long long\fP representation,
respectively. First, they shall decompose the input
string into three parts:
.IP " 1." 4
An initial, possibly empty, sequence of white-space wide-character
codes (as specified by \fIiswspace\fP())
.LP
.IP " 2." 4
A subject sequence interpreted as an integer represented in some radix
determined by the value of \fIbase\fP
.LP
.IP " 3." 4
A final wide-character string of one or more unrecognized wide-character
codes, including the terminating null wide-character
code of the input wide-character string
.LP
.LP
Then they shall attempt to convert the subject sequence to an integer,
and return the result.
.LP
If \fIbase\fP is 0, the expected form of the subject sequence is that
of a decimal constant, octal constant, or hexadecimal
constant, any of which may be preceded by a \fB'+'\fP or \fB'-'\fP
sign. A decimal constant begins with a non-zero digit, and
consists of a sequence of decimal digits. An octal constant consists
of the prefix \fB'0'\fP optionally followed by a sequence
of the digits \fB'0'\fP to \fB'7'\fP only. A hexadecimal constant
consists of the prefix 0x or 0X followed by a sequence of
the decimal digits and letters \fB'a'\fP (or \fB'A'\fP ) to \fB'f'\fP
(or \fB'F'\fP ) with values 10 to 15
respectively.
.LP
If the value of \fIbase\fP is between 2 and 36, the expected form
of the subject sequence is a sequence of letters and digits
representing an integer with the radix specified by \fIbase\fP, optionally
preceded by a \fB'+'\fP or \fB'-'\fP sign, but
not including an integer suffix. The letters from \fB'a'\fP (or \fB'A'\fP
) to \fB'z'\fP (or \fB'Z'\fP ) inclusive are
ascribed the values 10 to 35; only letters whose ascribed values are
less than that of \fIbase\fP shall be permitted. If the value
of \fIbase\fP is 16, the wide-character code representations of 0x
or 0X may optionally precede the sequence of letters and
digits, following the sign if present.
.LP
The subject sequence is defined as the longest initial subsequence
of the input wide-character string, starting with the first
non-white-space wide-character code that is of the expected form.
The subject sequence contains no wide-character codes if the
input wide-character string is empty or consists entirely of white-space
wide-character code, or if the first non-white-space
wide-character code is other than a sign or a permissible letter or
digit.
.LP
If the subject sequence has the expected form and \fIbase\fP is 0,
the sequence of wide-character codes starting with the first
digit shall be interpreted as an integer constant. If the subject
sequence has the expected form and the value of \fIbase\fP is
between 2 and 36, it shall be used as the base for conversion, ascribing
to each letter its value as given above. If the subject
sequence begins with a minus sign, the value resulting from the conversion
shall be negated. A pointer to the final wide-character
string shall be stored in the object pointed to by \fIendptr\fP, provided
that \fIendptr\fP is not a null pointer.
.LP
In other than the C  or POSIX  locales, other
implementation-defined subject sequences may be accepted.
.LP
If the subject sequence is empty or does not have the expected form,
no conversion shall be performed; the value of \fInptr\fP
shall be stored in the object pointed to by \fIendptr\fP, provided
that \fIendptr\fP is not a null pointer.
.LP
These functions shall not change the setting of \fIerrno\fP if successful.
.LP
Since 0, {LONG_MIN} or {LLONG_MIN} and {LONG_MAX} or {LLONG_MAX} are
returned on error and are also valid returns on success, an
application wishing to check for error situations should set \fIerrno\fP
to 0, then call \fIwcstol\fP() or \fIwcstoll\fP(), then
check \fIerrno\fP. 
.SH RETURN VALUE
.LP
Upon successful completion, these functions shall return the converted
value, if any. If no conversion could be performed, 0
shall be returned  and \fIerrno\fP may be set to indicate the error.
If the correct value is outside the range of representable values,
{LONG_MIN}, {LONG_MAX}, {LLONG_MIN}, or {LLONG_MAX} shall
be returned (according to the sign of the value), and \fIerrno\fP
set to [ERANGE].
.SH ERRORS
.LP
These functions shall fail if:
.TP 7
.B EINVAL
The value of \fIbase\fP is not supported. 
.TP 7
.B ERANGE
The value to be returned is not representable.
.sp
.LP
These functions may fail if:
.TP 7
.B EINVAL
No
conversion could be performed. 
.sp
.LP
\fIThe following sections are informative.\fP
.SH EXAMPLES
.LP
None.
.SH APPLICATION USAGE
.LP
None.
.SH RATIONALE
.LP
None.
.SH FUTURE DIRECTIONS
.LP
None.
.SH SEE ALSO
.LP
\fIiswalpha\fP(), \fIscanf\fP(), \fIwcstod\fP(), the Base Definitions
volume of IEEE\ Std\ 1003.1-2001, \fI<wchar.h>\fP
.SH COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. In the
event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online at
http://www.opengroup.org/unix/online.html .

Bell Labs OSI certified Powered by Plan 9

(Return to Plan 9 Home Page)

Copyright © 2021 Plan 9 Foundation. All Rights Reserved.
Comments to webmaster@9p.io.