Atomic portindex

[Ryan Schmidt]

I sometimes have to rebuild the PortIndex locally for testing, and  
since it takes minutes to do that, I might want to install some port  
while portindex is running. But this usually doesn't work because the  
port I want to install usually has dependencies, and the portindex  
script might not yet have gotten around to adding that port to the  
new PortIndex.

I think it would be nice for the portindex script to use a temporary  
file for the new index, and only move it over the existing PortIndex  
file when it's all through. Can anyone think of a reason why that  
wouldn't work or wouldn't be desirable?