freebsd-skq

History

yar bd7f6192a0 Add some essential tools to rescue(8) in order to make it a versatile emergency tool: o sed(1) as a multi-purpose text filter -- can do grep's job and much more. o head(1), tail(1), and tee(1) as idiomatic text filters. o mt(1) to control tape drives (PR misc/98383). o chown(8) aka chgrp(8) to complement the ch* subset. o pkill(1) aka pgrep(1) to control running processes easily and thus to be able to recover from a serious problem or a fatal typo in an otherwise live system w/o a reboot. (It also deserves adding to rescue(8) for its having triggered a latent bug in crunchgen(1), but we had better add a regression test for that. :-) The resulting change in rescue(8) size has the following order of magnitude on i386: 3787656 - 3727872 = 59784, i.e. just a tad. Discussed on: -hackers (I seem to have wearied all opponents :-) PR: misc/98383		2007-10-27 18:18:58 +00:00
..
librescue	Respect MK_INET6_SUPPORT.	2006-07-27 12:28:05 +00:00
rescue	Add some essential tools to rescue(8) in order to make it	2007-10-27 18:18:58 +00:00
Makefile
README

README

The /rescue build system here has three goals:

1) Produce a reliable standalone set of /rescue tools.

The contents of /rescue are all statically linked and do not depend on
anything in /bin or /sbin.  In particular, they'll continue to
function even if you've hosed your dynamic /bin and /sbin.  For
example, note that /rescue/mount runs /rescue/mount_nfs and not
/sbin/mount_nfs.  This is more subtle than it looks.

As an added bonus, /rescue is fairly small (thanks to crunchgen) and
includes a number of tools (such as gzip, bzip2, vi) that are not
normally found in /bin and /sbin.

2) Demonstrate robust use of crunchgen.

These Makefiles recompile each of the crunchgen components and include
support for overriding specific library entries.  Such techniques
should be useful elsewhere.  For example, boot floppies could use this
to conditionally compile out features to reduce executable size.

3) Produce a toolkit suitable for small distributions.

Install /rescue on a CD or CompactFlash disk, and symlink /bin and
/sbin to /rescue to produce a small and fairly complete FreeBSD
system.

These tools have one big disadvantage: being statically linked, they
cannot use some advanced library functions that rely on dynamic
linking.  In particular, nsswitch, locales, and pam are likely to all
rely on dynamic linking in the near future.


To compile:

# cd /usr/src/rescue
# make obj
# make
# make install

Note that rebuilds don't always work correctly; if you run into
trouble, try 'make clean' before recompiling.

$FreeBSD$