_read is a version of read designed to operate
only on HFS files. _read runs faster and calls
fewer other library routines than read. Refer to read
for a full description. _read is used exactly like the standard
read function. The first argument to _read must
be the file descriptor for an open HFS file.
Copyright (c) 1998 SAS Institute Inc. Cary, NC, USA. All rights reserved.