[Proj] How to Reengineering the cs2cs tool

[Karl Swartz]

> This means that you can't use something like:
> 
> 	while (more coordinates) {
> 		send input to cs2cs
> 		read output from cs2cs
> 	}

This sort of code is generally a bad idea as its behavior depends on the
OS and the program you are calling.

In the old days, I would have used a temp file, but now I'd consider
threads.

 -- Karl