CD

This is yet another CHDIR program. however it offers the following
features:

	1) it is written entirely in a high level lang..not DCL
	   hence it is much faster.

	2) it supports 2 syntaxes ...one for the UNIX (tm) diehards
	   and one that has cropped up in many DCL versions.

	   the following 3 commands are the same.

	    $ SET DEFAULT [--.FOO.BAR.SUB]

	    $ cd ../../foo/bar/sub

	    $ cd ^^foo.bar.sub

	3)  cd checks to see if the target directory is accessable
	    and issues an error if it is not...hence you cannot
	    cd into nonexistant or protected directories.

	3)  cd has a built in help which is invoked by:

		$ cd ?

	4)  Cd has a mechanism to allow for simple hopping about in 
	    system directory...it translates the logical names 
	    SYS$SYSROOT and SYS$SYSDEVICE so these commands will
	    work on any normal VMS rooted system directory tree
	    on any system device. CD ? will list the system tree commands

	disadvantages:

	1)  it must be defined as a foreign command. (CLD definitions
	    work poorly because DCL has special interpretations of the "/"
            character.  place the following line in SYLOGIN.COM or
	    individual LOGIN.COM routines.

		cd == "$disk:[directory]cd"  ! where ever you put cd

	 2) It has a site specific syntax to change directory to
	    a volume called "LIB$DISK" (this can be changed inthe source)


	required files:

		CD.FOR		source
		CDMESS.MSG	error message definition
		CD.RNO, CD.MEM	User guide
		MAKCD.COM	Routine to compile and link CD