file descriptors --> filenames

[guyton%rand-unix at sri-unix.UUCP]

From:  James_Guyton <guyton at rand-unix>

The only "practical" way of doing this is to hang onto the
filename yourself when you do the open (and forget it when
you close).

This isn't a general solution for Unix programs (since you
can be passed open files via stdin, stdout, stderr, pipes,
etc.), but if you're converting a pgm from RSX, that
shouldn't be a problem for you.  You might also run into
problems if the program ever changes its current working
directory after an open.

I suggest having an array of strings indexed by the real
file descriptor ("fileno" of the FILE argument).  Use the
variable NOFILE out of <sys/param.h> for the size of the
array.

-- Jim