Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Extend kldunload(8) functionality and fix minor problems:
o multiple modules can be unloaded at once (specified either by id or be
module name)
o exit with EX_USAGE after usage() is called.
o remove unused variables, since we keep command line flags as bitmask,
in 'opt'.
o 'kldload -n ...' does nothing. Add comment to this options.

Additionally:
o Update manual page to conform new functionality.
o Increace WARNS to 6. Because we can.

Approved by: cognet (mentor)
MFC after: 1 week

Big style(9) fix. This commit brings no functional change.

Approved by: cognet (mentor)
MFC after: 1 week

Document -f in usage().

Give kldunload a -f(orce) argument.

Add a MOD_QUIESCE event for modules. This should return error (EBUSY)
of the module is in use.

MOD_UNLOAD should now only fail if it is impossible (as opposed to
inconvenient) to unload the module. Valid reasons are memory references
into the module which cannot be tracked down and eliminated.

When kldunloading, we abandon if MOD_UNLOAD fails, and if -force is
not given, MOD_QUIESCE failing will also prevent the unload.

For backwards compatibility, we treat EOPNOTSUPP from MOD_QUIESCE as
success.

Document that modules should return EOPNOTSUPP for unknown events.

Use __FBSDID() to quiet GCC 3.3 warnings.

style(9): use NULL when assigning/comparing a char *,
consitently compare fileid with 0 using == and !=.

Reviewed by: silence on @audit

Make this WARNS=5 clean by adding () in 'if (a || (b && c))'.

Look at by: sebastian.ssmoller@web.de on audit@

Fixed bitrot in usage message (-n is now optional).

$Id$ -> $FreeBSD$

Add a sensible message if an invalid ID was entered

PR: 8739
Submitted by: Love lha@stacken.kth.se
Reviewed by: Doug Rabson <doug@freebsd.org>

Bitch if both an id and a name are specified. Make the man page and usage
message reflect this. As a bonus, make the -n optional so that 'kldunload
name' works as one would expect.

Lowercase 1st char. in err(3) strings.

Sync. usage string and synopsis. Add rcsid.

fix mispelling of kld

a few code style changes:
o start function names in column 1
o sort order of flags in getopt and switch
o don't try to reference progname
o unspam some changes introduced by a 2.2.1-R build box instead of a
-current build box

doc changes:
o document when these commands first appeared
o put email address in angle brakets
o minor mdoc clean up

activate the programs that will be used to manipulate kld modules

fix a few problems with missing headers, warn called with an exit
value, and undeclared getopt vars

these programs now compile -Wall clean (and yes, I know I should use
more than just -Wall) :)

Add utilities for the kernel linker.