>>>Reentrancy: A program that may be called by another while it is already in the calling stack;
>>>
>>
>>PMJI Jim,
>>It's been a long time since the theory classes but I thought 'reentrant' simply meant that more than one pointer (IP?) to a current program line is allowed, thus allowing more than one process to be using the same program code.
>>Does that ring a bell?
>>(Please tell me to go jump if i've missed the point here)
>
>David,
>
>It may be, I remember it as a program being able to be called from another while that program is in the calling stack, which would require what you said to allow it. Recursion, though, is a program directly calling itself, which also requires the ability you mentioned.

Hi Jim,
I could imagine recursion being implemented without multiple program pointers. Just a special arrangement of the calling stack. That is even though there's recursion there's only one line of code which is being (or about to be) executed at any one time.