Footnotes

(1)

The term bootstrapping refers to a Dutch legend about a boy who was able to fly by pulling himself up by his bootstraps. In computers, this term refers to any process where a simple system activates a more complicated system.

(2)

The GRand Unified Bootloader, available from http://www.uruk.org/grub/.

(3)

In the Hurd system, we don't make the assumption that MACH_PORT_NULL is zero and evaluates to false, but rather compare port names to MACH_PORT_NULL explicitely

(4)

Sending out-of-line memory with a non-page-aligned address, or a size which is not a page multiple, works but with a caveat. The extra bytes in the first and last page of the received memory are not zeroed, so the receiver can peek at more data than the sender intended to transfer. This might be a security problem for the sender.

(5)

If MACH_SEND_TIMEOUT is used without MACH_SEND_INTERRUPT, then the timeout duration might not be accurate. When the call is interrupted and automatically retried, the original timeout is used. If interrupts occur frequently enough, the timeout interval might never expire.

(6)

If MACH_RCV_TIMEOUT is used without MACH_RCV_INTERRUPT, then the timeout duration might not be accurate. When the call is interrupted and automatically retried, the original timeout is used. If interrupts occur frequently enough, the timeout interval might never expire.