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-.\" Copyright (c) 2022 by Alejandro Colomar <alx@kernel.org>
-.\"
-.\" SPDX-License-Identifier: Linux-man-pages-copyleft
-.\"
-.\"
-.TH NULL 3const 2023-10-31 "Linux man-pages 6.7"
-.SH NAME
-NULL \- null pointer constant
-.SH LIBRARY
-Standard C library
-.RI ( libc )
-.SH SYNOPSIS
-.nf
-.B #include <stddef.h>
-.P
-.B "#define NULL ((void *) 0)"
-.fi
-.SH DESCRIPTION
-.B NULL
-represents a null pointer constant,
-that is, a pointer that does not point to anything.
-.SH CONFORMING TO
-C99 and later;
-POSIX.1-2001 and later.
-.SH NOTES
-The following headers also provide
-.BR NULL :
-.IR <locale.h> ,
-.IR <stdio.h> ,
-.IR <stdlib.h> ,
-.IR <string.h> ,
-.IR <time.h> ,
-.IR <unistd.h> ,
-and
-.IR <wchar.h> .
-.SH CAVEATS
-It is undefined behavior to dereference a null pointer,
-and that usually causes a segmentation fault in practice.
-.P
-It is also undefined behavior to perform pointer arithmetic on it.
-.P
-.I NULL \- NULL
-is undefined behavior, according to ISO C, but is defined to be 0 in C++.
-.P
-To avoid confusing human readers of the code,
-do not compare pointer variables to
-.BR 0 ,
-and do not assign
-.B 0
-to them.
-Instead, always use
-.BR NULL .
-.P
-.B NULL
-shouldn't be confused with
-.BR NUL ,
-which is an
-.BR ascii (7)
-character,
-represented in C as
-.BR \[aq]\e0\[aq] .
-.SH BUGS
-When it is necessary to set a pointer variable to a null pointer,
-it is not enough to use
-.BR memset (3)
-to zero the pointer
-(this is usually done when zeroing a struct that contains pointers),
-since ISO C and POSIX don't guarantee that a bit pattern of all 0s
-represent a null pointer.
-See the EXAMPLES section in
-.BR getaddrinfo (3)
-for an example program that does this correctly.
-.SH SEE ALSO
-.BR void (3type)