Take Command

HFS Utilities

Data on Macintosh disks can be read into Linux quite easily with this package of tools.

by Marjorie Richardson

Macintosh users may be a minority, but they are quite loyal to their operating system and loathe to give it up. Mac OS stores its files in HFS (hierarchical file system) format, which uses a return character to separate lines in text files, rather than a newline character as in Linux/UNIX. If you have files on a Macintosh floppy disk that you wish to get on your Linux system, several options are available.

Just as ``m'' commands deal with DOS disks, ``h'' commands work for Macintosh disks. These commands are named and behave just as any Linux user might expect. For example, to change directories on your Linux system, you type cd path; to do so with a Mac volume, you type hcd path. In other words, you just add an ``h'' as the first character of the command name. In some cases, the base command name is taken from DOS rather than UNIX--I guess to make the h tools consistent with the m tools. The most frequently used h utilities are:

hcd path: change working directory on the disk; default is the root (/) directory
hdel names: delete a file or files on the disk
hcopy source destination: copy a file to or from an HFS disk
hdir: list the files on the disk; hls also works for this purpose
hmkdir path: create a directory on the disk; hrmdir removes a directory on the disk
hmount device_name: mount the HFS disk at this location; humount unmounts the disk

Other available commands are hformat, hpwd, hrename, hvol and hatrib. For details on these HFS utilities and their options, see the man pages.

Wild cards are permitted in specifying path names, but be aware that if you use ``*'' to mean ``every file in the directory'', it will not be interpreted that way. For example, typing hcopy * . will look for the filenames on the HFS floppy in the current directory , instead of getting all the files off the HFS floppy as you would expect.

Another method for manipulating Mac disks is the hfs shell. This shell, based on Tcl, provides the same type of options as the h commands: mount (m), umount (u), cd (c), dir (d), mkdir (m), rmdir (r), etc. The difference is only in the way the command is specified. For example, to mount the disk with hfs, you type:

hfs m

instead of

hmount

Finally, Robert Leslie's program xhfs provides a graphical user interface to the hfs commands. It is easy to use and quite intuitive. Just type:

xhfs

and up pops a window displaying available options (see Figure 1). A click of the mouse on the button next to the option you want, and you are on your way to having those files on your system in Linux format.

If a friend sends you a Macintosh file, don't forget you need to get rid of those pesky return characters. The tr command (see ``A Little Devil Called tr'' by Hans de Vreught, LJ, September 1998) is the best tool for doing this. Typing

tr '\015' '\012' <

will do the trick.

Another good resource for these commands and others is Linux for Dummies Quick Reference, 2nd Edition by Phil Hughes.

Marjorie Richardson (ljeditor@ssc.com) is Editor in Chief of Linux Journal. A movie aficionado, she is currently enamored of DVD technology and can't bear to watch movies ``that have been formatted for your TV screen''.