+++ /dev/null
-.\" Copyright (c) 1980, 1991 Regents of the University of California.
-.\" All rights reserved.
-.\"
-.\" %%%LICENSE_START(BSD_4_CLAUSE_UCB)
-.\" Redistribution and use in source and binary forms, with or without
-.\" modification, are permitted provided that the following conditions
-.\" are met:
-.\" 1. Redistributions of source code must retain the above copyright
-.\" notice, this list of conditions and the following disclaimer.
-.\" 2. Redistributions in binary form must reproduce the above copyright
-.\" notice, this list of conditions and the following disclaimer in the
-.\" documentation and/or other materials provided with the distribution.
-.\" 3. All advertising materials mentioning features or use of this software
-.\" must display the following acknowledgement:
-.\" This product includes software developed by the University of
-.\" California, Berkeley and its contributors.
-.\" 4. Neither the name of the University nor the names of its contributors
-.\" may be used to endorse or promote products derived from this software
-.\" without specific prior written permission.
-.\"
-.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
-.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
-.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
-.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
-.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
-.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
-.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
-.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
-.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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-.\" %%%LICENSE_END
-.\"
-.\" @(#)alloca.3 5.1 (Berkeley) 5/2/91
-.\"
-.\" Converted Mon Nov 29 11:05:55 1993 by Rik Faith <faith@cs.unc.edu>
-.\" Modified Tue Oct 22 23:41:56 1996 by Eric S. Raymond <esr@thyrsus.com>
-.\" Modified 2002-07-17, aeb
-.\" 2008-01-24, mtk:
-.\" Various rewrites and additions (notes on longjmp() and SIGSEGV).
-.\" Weaken warning against use of alloca() (as per Debian bug 461100).
-.\"
-.TH ALLOCA 3 2013-10-07 "GNU" "Linux Programmer's Manual"
-.SH NAME
-alloca \- allocate memory that is automatically freed
-.SH SYNOPSIS
-.B #include <alloca.h>
-.sp
-.BI "void *alloca(size_t " size );
-.SH DESCRIPTION
-The
-.BR alloca ()
-function allocates
-.I size
-bytes of space in the stack frame of the caller.
-This temporary space is
-automatically freed when the function that called
-.BR alloca ()
-returns to its caller.
-.SH RETURN VALUE
-The
-.BR alloca ()
-function returns a pointer to the beginning of the allocated space.
-If the allocation causes stack overflow, program behavior is undefined.
-.SH ATTRIBUTES
-.SS Multithreading (see pthreads(7))
-The
-.BR alloca ()
-function is thread-safe.
-.SH CONFORMING TO
-This function is not in POSIX.1-2001.
-
-There is evidence that the
-.BR alloca ()
-function appeared in 32V, PWB, PWB.2, 3BSD, and 4BSD.
-There is a man page for it in 4.3BSD.
-Linux uses the GNU version.
-.SH NOTES
-The
-.BR alloca ()
-function is machine- and compiler-dependent.
-For certain applications,
-its use can improve efficiency compared to the use of
-.BR malloc (3)
-plus
-.BR free (3).
-In certain cases,
-it can also simplify memory deallocation in applications that use
-.BR longjmp (3)
-or
-.BR siglongjmp (3).
-Otherwise, its use is discouraged.
-
-Because the space allocated by
-.BR alloca ()
-is allocated within the stack frame,
-that space is automatically freed if the function return
-is jumped over by a call to
-.BR longjmp (3)
-or
-.BR siglongjmp (3).
-
-Do not attempt to
-.BR free (3)
-space allocated by
-.BR alloca ()!
-.SS Notes on the GNU version
-Normally,
-.BR gcc (1)
-translates calls to
-.BR alloca ()
-with inlined code.
-This is not done when either the
-.IR "\-ansi" ,
-.IR "\-std=c89" ,
-.IR "\-std=c99" ,
-or the
-.IR "\-std=c11"
-option is given
-.BR and
-the header
-.I <alloca.h>
-is not included.
-Otherwise, (without an \-ansi or \-std=c* option) the glibc version of
-.I <stdlib.h>
-includes
-.I <alloca.h>
-and that contains the lines:
-.nf
-
- #ifdef __GNUC__
- #define alloca(size) __builtin_alloca (size)
- #endif
-
-.fi
-with messy consequences if one has a private version of this function.
-.LP
-The fact that the code is inlined means that it is impossible
-to take the address of this function, or to change its behavior
-by linking with a different library.
-.LP
-The inlined code often consists of a single instruction adjusting
-the stack pointer, and does not check for stack overflow.
-Thus, there is no NULL error return.
-.SH BUGS
-There is no error indication if the stack frame cannot be extended.
-(However, after a failed allocation, the program is likely to receive a
-.B SIGSEGV
-signal if it attempts to access the unallocated space.)
-
-On many systems
-.BR alloca ()
-cannot be used inside the list of arguments of a function call, because
-the stack space reserved by
-.BR alloca ()
-would appear on the stack in the middle of the space for the
-function arguments.
-.SH SEE ALSO
-.BR brk (2),
-.BR longjmp (3),
-.BR malloc (3)
-.SH COLOPHON
-This page is part of release 3.79 of the Linux
-.I man-pages
-project.
-A description of the project,
-information about reporting bugs,
-and the latest version of this page,
-can be found at
-\%http://www.kernel.org/doc/man\-pages/.
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