cd - Change working directory
cd ?dirName?
Change the current working directory to dirName, or to the
home directory (as specified in the HOME environment variable) if
dirName is not given.
Returns an empty string.
working directory
Copyright © 1993 The Regents of the University of California.
Copyright © 1994-1996 Sun Microsystems, Inc.
Copyright © 1995, 1996 Roger E. Critchlow Jr.