The Linux File System

Linux System Security

All users must login with a user name and password which then maps user processes into a user id (uid).
All files throughout the file system belong to a particular uid and gid and are associated with a access code.
The access rights of a file can be set using the chmod program.
Process access right checks:

Command	Purpose
ls	a directory listing
rm	delete a file or directory
mv	move a file from one place to another
cp	copy a file from one place to another
ln	link a file
chmod	change file permissions
find	locate files

Command	Purpose
fsck	check to make sure a filesystem is working o.k.
mount / umount	mount and unmount filesystems from the directory tree
mke2fs	'format' a device / partition
du & df	partition space available