hi folks.

i've changed the swapctl(2) system call as follows:

	- the SWAP_STATS command has been renamed SWAP_OSTATS,
	  and it is only supported with the COMPAT_13 kernel
	  option.
	- a new SWAP_STATS command has been added.  the news
	  SWAP_STATS uses a larger `struct swapent' that includes
	  space for a pathname (se_path).

swapctl(8) has been updated to use the returned pathname rather
than trying to find it in /dev with devname(3).  this also means
that swapfiles can be shown by `swapctl -l'.

these changes do not affect source compatibility, nor ABI
compatibility (as the new command has a different value), and old
binaries will continue to work if COMPAT_13 is used.


i've tested this fairly heavily under UVM, but as i don't have
any machines running -current that support oldvm, i have only
tried these changes on an i386 running 1.3.2 with -current oldvm
kernel, with both a 1.3.2 swapctl(8) and mostly -current
swapctl(8).

NOTE: if COMPAT_13 is not used, an old `swapctl -l' will show
strange errors, as there was a minor bug in swapctl(8) that
only shows up if swapctl(SWAP_STATS, ...) fails.


as usual, please report any problems you see with send-pr(1)
and i will attend to them ASAP.


(note: updates for options.4 and swapctl.2 are forthcoming).