The cd←link Program: The 'cd←link' program, creates a set of symbolic links from a specified target directory to the files/directories stored on a CD-ROM created by 'Makedisc', ISO/Rock Ridge Formatting Software from Young Minds, Inc.. The program uses a 'cdrom←directory' to search for a translation file (for example, YMTRANS.TBL). If found the program uses the translation file to build a set of symbolic links to the other files (and directories if the '-r' option is given) in the cdrom←directory, using the original UNIX-style file and directory names for the links. This utility is particularly useful for compiling source code straight off of the CD-ROM disc or for having access to known UNIX-style libraries without having to load them off the CD-ROM onto your hard disk. Usage for cd←link is as follows: cd←link [-rR] [cdrom←directory] [target directory] The -r option will recursively descend the subdirectory rooted at cdrom←directory creating links at each level. The -R option is for use with a Rock Ridge driver and will create links to an image with Rock Ridge extensions. The following example demonstrates how to create the symbolic links necessary to recreate the directory tree for gnuplot in the directory '~my←account/gnuplot' (where the CD-ROM image has been mounted as '/cd-rom←disc'): cd ~my←account Move to the ~my←account directory. In order to support as many end users of CD-ROM as possible, (some of which are probably unanticipated) the cd←link utility is provided in source form. So, if binaries are not present on your platform, you can create them by compiling the source code with a standard ANSI C compiler (available on most UNIX platforms). First, copy the source to your current directory: cp /cd-rom/ym←utils/"cd←link.c;1" cd←link.c The quotes around the cd←link.c;1 are necessary to prevent the shell from interferring with the operation. Next, enter: cc -o cd←link cd←link.c This will create an executable called cd←link. On some platforms it may be necessary to link in a BSD compatibility library. Check with your system administrator or operating system documentation to see if this is the case for your machine. If so, to get cd←link to compile you should enter the following command: cc -o cd←link cd←link.c /usr/lib/libBSD.a Once you have an executable, enter the following commands: mkdir gnuplot Create the gnuplot directory to use in recreating the directory tree. cd gnuplot Move to the gnuplot directory. ../cd←link -r /cd-rom←disc/x11r2/gnuplot or, if you want to direct output to the gnuplot directory from elsewhere, try: cd←link -r /cd-rom←disc/x11r5/gnuplot <PATH>/gnuplot where <PATH> is the path to the gnuplot directory. It will take a little while, but once it's finished, listing the contents of your gnuplot directory will now show the files in the gnuplot directory on the CD-ROM, except that the original UNIX filenames will appear instead of the actual, translated filenames on the CD-ROM. If you want to see how they are different, you save the listings of both your gnuplot directory and the one on the CD-ROM to files and apply the 'diff' utility. NOTE: While all filenames on CD-ROM discs from Young Minds, Inc. are stored using uppercase letters, some CD-ROM file system drivers will automatically convert the filename characters to lowercase. The directory 'cdrom←directory' need not reside on a CD-ROM disc, as long as it contains a copy of all files from a directory on a CD-ROM disc (and that directory's subdirectories if you wish to use the -r option). Also, while the current version of Makedisc generates translation table entries for block device nodes, character device nodes, pipes and sockets (denoted as B, C, P, and S), the current version of cd←link ignores these entries since there is as yet no well-defined, machine-independant mapping for these entries. NOTE: While there is no reason why the program could not be useful in making directory trees of symbolic links to arbitrary directories, the required translation file only allows the program to be used on a directory (or directory tree) that contains correct translation files. Once you have successfully created the executable, you may wish to store it in some commonly accessible location like '/usr/local/bin'.