Returns a pointer to a newly allocated chunk of at least n
bytes, or null if no space is available. Additionally, on
failure, errno is set to ENOMEM on ANSI C systems.
If n is zero, malloc returns a minimum-sized chunk. (The
minimum size is 16 bytes on most 32bit systems, and 24 or 32
bytes on 64bit systems.) On most systems, size_t is an unsigned
type, so calls with negative arguments are interpreted as
requests for huge amounts of space, which will often fail. The
maximum supported value of n differs across systems, but is in
all cases less than the maximum representable value of a