On 26.05.2008 23:52, Cheyne Li wrote:
> How can I capture a error massage from the STD IO?
> For instance, I have a program call foo.exe and i run the program
> /foo.exe
> 
> Then the program prints out some error messages.
> 
> How can I write a script that capture the errors and save then into a
> file?

You do not need Ruby for that.  At an arbitrary shell prompt:

foo.exe > errors.txt

Kind regards

	robert