Portable way of finding libc, unbuffered reads

[Clinton A. Pierce]

The following code works just fine:

        loadlib P1, "/lib/libc.so.6"
        dlfunc P0, P1, "system", "it"
        set I0, 1
        set S5, "ls"
        invoke
        end
(Which in itself tickles and scares the bejesus out of me.)  Is there a 
good way of finding the standard C library on a Unix system other than 
hard-wiring it in like this?

Also, is there any way yet of getting an unbuffered read (in parrot) so I 
can getc() from the keyboard?  I should ask, is there an *approved* way of 
doing that now?  I'm fairly familiar with C's I/O model so I could pull it 
off with ioctl(), fcntl(), etc... and all of their friends, but alas 
they're not around yet.

These questions are not necessarily related.  Or unrelated.  :)