[Pythonmac-SIG] What is a bus error, anyway?

[Jack Jansen]

On Tuesday, July 16, 2002, at 04:09 , Andrew Straw wrote:

> Hi all,
>
> For so long I've accepted the fact that I can't run python on Mac OS X 
> twice simultaneously because of the dreaded "bus error".  But why? What 
> is a bus error?

The "bus error" in this case is just a symptom. (What it usually means 
is that a program tries to write to either a non-existing memory 
address, or write a 4-byte quantity to an address that isn't a 4-byte 
multiple. In other words: the program in question has completely fouled 
up it's data structures).

But, that aside: what exactly are you doing that you get a bus error? If 
you're running python twice from the commandline there should be 
absolutely no problem. If you try to run Python.app twice by 
double-clicking on a second .py script while the first one is still 
running it doesn't work, but I woulnd't expect a bus error (I would 
expect nothing to happen).
--
- Jack Jansen        <Jack.Jansen@oratrix.com>        
http://www.cwi.nl/~jack -
- If I can't dance I don't want to be part of your revolution -- Emma 
Goldman -