This article is from the MachTen & CodeBuilder FAQ, by Jaime Julca firstname.lastname@example.org with numerous contributions by others.
In general, since MachTen is a pure BSD UNIX, porting applications is
relatively straightforward. However, in real-memory MachTen systems, such as
Power MachTen, some porting issues can arise. Without protected memory, a
bad pointer can bring down your entire machine. Additionally, it may become
necessary, during the execution of a process, to grow the size of a segment
to accomodate a larger stack. This is not a problem on a virtual memory
system such as Professional MachTen. However, with Power MachTen (before VM
is supported), you may need to make certain accommodations. See section
10.13 in the Power MachTen User's Guide for more inforomation.