/usr/src/virtualbox-guest-4.1.42/include/iprt/ is in virtualbox-guest-dkms 4.1.42-dfsg-1+deb7u1.
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/usr/src/virtualbox-guest-4.1.42/include/iprt/alloc.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/alloca.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/asm-amd64-x86.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/asm-math.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/asm.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/assert.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/avl.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/cdefs.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/cpuset.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/ctype.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/err.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/fs.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/heap.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/initterm.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/list.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/lockvalidator.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/log.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/mangling.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/mem.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/memobj.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/mp.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/net.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/nocrt/
/usr/src/virtualbox-guest-4.1.42/include/iprt/nocrt/limits.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/param.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/path.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/power.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/process.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/semaphore.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/spinlock.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/stdarg.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/stdint.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/string.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/thread.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/time.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/types.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/uni.h
/usr/src/virtualbox-guest-4.1.42/include/iprt/x86.h