[CentOS] How does Live CD find OS's?

Chris Murphy wrote:

> Live CD does not have a troubleshoot boot sub menu option.

If I boot into CentOS-7-x86_64-LiveKDE-1503.iso
there is a Troubleshooting option, and if I choose this
there is an option to "Boot into Local Disk".
Clicking on this gives a list of OS's to boot into.

It seems this does run through all partitions,
running os-prober on each.
I thought os-prober was an object file, but I see it is a bash script,
so hopefully I can see exactly what it does.

-- 
Timothy Murphy  
gayleard /at/ eircom.net
School of Mathematics, Trinity College, Dublin