Undocumented malloc(3) features query

[Sam Kendall]

The WARNINGS section of the malloc(3X) manual page under System V.2
says: "Undocumented features of malloc(3C) have not been duplicated."
(Malloc(3X) is an alternate implementation of malloc.)

Does anyone know what these undocumented features are?  They probably
pertain to the global variables named things like `allocx' which
are brought in from libc along with malloc.

This is not just idle curiosity.  To know this would be useful for a
current project.  Respond by mail; I'll summarize to the net.

	Sam Kendall	{allegra,ihnp4,ima,amd70}!wjh12!kendall
	Delft Consulting Corp.	    decvax!genrad!wjh12!kendall