Installing on a read only file system

["D'Arcy J.M. Cain" <darcy%NetBSD.org@localhost>]

I am trying to set up my NetBSD build system on a read only file
system.  However, it still tries to write into the CVS repository.
Here are the directives in /etc/mk.conf that reference directories:

WRKDIRPREFIX=/usr/obj
DISTDIR=/usr/distfiles
PACKAGES=/usr/packages
BUILDIR = /usr/obj/build
LOCALBASE =                     /usr/pkg
WRKOBJDIR =                     /usr/obj
PKGSRCDIR =                     /usr/pkgsrc
PACKAGES =                      /usr/packages
TOOLDIR =                       /usr/obj/tools
MAKEOBJDIR =                    /usr/obj
OBJMACHINE =                    /usr/obj
BSDOBJDIR =                     /usr/obj
RELEASEDIR =                    /usr/obj/release
DESTDIR =                       /usr/obj/destdir
X11BASE =                       /usr/X11R7

However, a "./build.sh tools" results in the following.  Am I missing
another variable?

...
dependall-host-mkdep ===> .     (with: dependall-compat dependall-binstall)
dependall ===> host-mkdep
rm -f host-mkdep
CC=cc  /bin/sh /usr/src/tools/host-mkdep/configure --cache-file=config.cache
/usr/src/tools/host-mkdep/configure: cannot create conf21587.file: read-only 
file system
/usr/src/tools/host-mkdep/configure: cannot create config.log: read-only file 
system

*** Failed target:  host-mkdep
*** Failed command: CC=cc /bin/sh /usr/src/tools/host-mkdep/configure 
--cache-file=config.cache
*** Error code 2

-- 
D'Arcy J.M. Cain <darcy%NetBSD.org@localhost>
http://www.NetBSD.org/ IM:darcy%Vex.Net@localhost