specifies the identifier
that was assigned when the directory was opened, generally by the
DOPEN function.
nval
specifies the sequence
number of the information item.
Details
Under UNIX, the only
directory information item available is Directory, which is the pathname
of the directory-id. The nval,
or sequence number, of Directory is 1. If directory-id points
to a list of concatenated directories, then Directory is the list
of concatenated directory names.