HEADS UP - statvfs() changes require buildworld/kernel/install

[Matthew Dillon]

    I recommend doing a full buildworld/buildkernel/installworld/installkernel
    sequence for those people running HEAD.

    I have implemented statvfs() in the kernel and removed it from libc.
    Not much uses statvfs() yet so the system will still boot, but it's 
    a good idea to fully synchronize your kernel and world anyhow.

    Note that you cannot just recompile libc.  Because new system calls were
    added updated headers are required for libc to properly build.

    statvfs() is a POSIX call which implements 64 bit fields for filesystem
    information.  statfs() only implements 32 bit fields.  Needless to say,
    32 bit fields are not going to work for terrabyte-sized filesystems.

						-Matt