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ALLOCA(3)		    Library Functions Manual		     ALLOCA(3)

NAME
       alloca -- memory	allocator

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	 allo-
       cated 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 er-
       ror.  Avoid alloca() with large unbounded allocations.

FreeBSD	15.0			April 29, 2025			     ALLOCA(3)

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<https://man.freebsd.org/cgi/man.cgi?query=alloca&manpath=FreeBSD+15.0-RELEASE+and+Ports>

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