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ALLOCA(3) FreeBSD Library Functions Manual ALLOCA(3)
NAME
alloca - memory allocator
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <stdlib.h>
void *
alloca(size_t size);
DESCRIPTION
The alloca() function allocates size bytes of space in the stack frame of
the caller. This temporary space is automatically freed on return.
RETURN VALUES
The alloca() function returns a pointer to the beginning of the allocated
space.
SEE ALSO
brk(2), calloc(3), getpagesize(3), malloc(3), realloc(3)
HISTORY
The alloca() function appeared in Version 7 AT&T UNIX/32V.
BUGS
The alloca() function is machine and compiler dependent; its use is
discouraged.
The alloca() function is slightly unsafe because it cannot ensure that
the pointer returned points to a valid and usable block of memory. The
allocation made may exceed the bounds of the stack, or even go further
into other objects in memory, and alloca() cannot determine such an
error. Avoid alloca() with large unbounded allocations.
FreeBSD 14.0-RELEASE-p6 September 5, 2006 FreeBSD 14.0-RELEASE-p6