03-22-2002
Here are the basics, you may want to check out the "FAQ" section for recommendations on beginners books that will provide a lot more information.
Every file on the system has an "owner" and a "group" that it belongs to. These are stored on disk as integers, and are mapped to human readable names using the /etc/passwd file and /etc/group file. Each file also has a set of permissions controlling who can access it. There are three sets of permissions for each file: user, group, and world (everyone else). For each set there are three (not strictly accurate, but I'm sticking to basics here) attributes that can be set: read permission, write permission, and execute permission. These are displayed when you do a long listing with "ls -l".
example:
$ ls -l test
-rwxrwxr-x 1 foo users 13780 Mar 13 13:18 test
So the permissions on this file grant read, write and execute to the user (foo) and group (users), and read & execute to anyone else.
You modify these file attributes using the "chmod", "chown" and "chgrp" commands. Please refer to the respective man pages for details.
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LEARN ABOUT POSIX
macutil
MACUTIL(1) General Commands Manual MACUTIL(1)
NAME
macutil - A package that deals with MacIntosh files on a Unix system
DESCRIPTION
macutil is a package that contains a number of utilities that deal with MacIntosh files on a Unix system. It contains the following pro-
grams:
binhex Convert files to BinHex 4.0 compatible hexified form.
frommac
Receives files from the MacIntosh on the Unix system.
hexbin Convert hexified files to their MacIntosh format.
macsave
Save a series of files from a MacBinary stream as individual files.
macstream
Combine a series of files to a MacBinary stream.
macunpack
Unpack a MacIntosh archive into its constituents.
tomac Transmits files from the Unix system to a MacIntosh.
BUGS
This manual page is hopelessly incomplete!
SEE ALSO
binhex(1), frommac(1), hexbin(1), macsave(1), macstream(1), macunpack(1), tomac(1)
AUTHOR
Dik T. Winter, CWI, Amsterdam, The Netherlands (dik@cwi.nl)
3rd Berkeley Distribution October 22, 1992 MACUTIL(1)