mirror of https://github.com/mkerrisk/man-pages
73 lines
2.5 KiB
Plaintext
73 lines
2.5 KiB
Plaintext
.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved
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.TH "<stddef.h>" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual"
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.\" <stddef.h>
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.SH NAME
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stddef.h \- standard type definitions
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.SH SYNOPSIS
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.LP
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\fB#include <stddef.h>\fP
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.SH DESCRIPTION
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.LP
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The \fI<stddef.h>\fP header shall define the following macros:
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.TP 7
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NULL
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Null pointer constant.
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.TP 7
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offsetof(\fItype\fP, \fImember-designator\fP)
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.sp
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Integer constant expression of type \fBsize_t\fP, the value of which
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is the offset in bytes to the structure member
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(\fImember-designator\fP), from the beginning of its structure (\fItype\fP).
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.sp
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.LP
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The \fI<stddef.h>\fP header shall define the following types:
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.TP 7
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\fBptrdiff_t\fP
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Signed integer type of the result of subtracting two pointers.
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.TP 7
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\fBwchar_t\fP
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Integer type whose range of values can represent distinct wide-character
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codes for all members of the largest character set
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specified among the locales supported by the compilation environment:
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the null character has the code value 0 and each member of
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the portable character set has a code value equal to its value when
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used as the lone character in an integer character
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constant.
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.TP 7
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\fBsize_t\fP
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Unsigned integer type of the result of the \fIsizeof\fP operator.
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.sp
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.LP
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The implementation shall support one or more programming environments
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in which the widths of \fBptrdiff_t\fP, \fBsize_t\fP,
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and \fBwchar_t\fP are no greater than the width of type \fBlong\fP.
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The names of these programming environments can be obtained
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using the \fIconfstr\fP() function or the \fIgetconf\fP utility.
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.LP
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\fIThe following sections are informative.\fP
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.SH APPLICATION USAGE
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.LP
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None.
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.SH RATIONALE
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.LP
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None.
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.SH FUTURE DIRECTIONS
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.LP
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None.
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.SH SEE ALSO
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.LP
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\fI<wchar.h>\fP , \fI<sys/types.h>\fP , the System
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Interfaces volume of IEEE\ Std\ 1003.1-2001, \fIconfstr\fP(), the
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Shell and
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Utilities volume of IEEE\ Std\ 1003.1-2001, \fIgetconf\fP
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.SH COPYRIGHT
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Portions of this text are reprinted and reproduced in electronic form
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from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
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-- Portable Operating System Interface (POSIX), The Open Group Base
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Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
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Electrical and Electronics Engineers, Inc and The Open Group. In the
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event of any discrepancy between this version and the original IEEE and
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The Open Group Standard, the original IEEE and The Open Group Standard
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is the referee document. The original Standard can be obtained online at
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http://www.opengroup.org/unix/online.html .
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