26.10.2012 Views

SUSE LINUX Documentation - Index of

SUSE LINUX Documentation - Index of

SUSE LINUX Documentation - Index of

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

104 Start-Up<br />

This column consists <strong>of</strong> one leading character followed by nine characters grouped<br />

in threes. The first <strong>of</strong> the ten letters stands for the type <strong>of</strong> file system component.<br />

The hyphen (–) shows that this is a file. A directory (d), a link (l), a block device<br />

(b), or a character device could also be indicated.<br />

The next three blocks follow a standard pattern. The first three characters refer to<br />

whether the file is readable (r) or not (–). A w in the middle portion symbolizes<br />

that the corresponding object can be edited and a hyphen (–) means it is not possible<br />

to write to the file. An x in the third position denotes that the object can be executed.<br />

Because the file in this example is a text file and not one that is executable, executable<br />

access for this particular file is not needed.<br />

In this example, tux has, as owner <strong>of</strong> the file Roadmap, read (r) and write access<br />

(w) to it, but cannot execute it (x). The members <strong>of</strong> the group project3 can read<br />

the file, but they cannot modify it or execute it. Other users do not have any access<br />

to this file. Other permissions can be assigned by means <strong>of</strong> ACLs (access control<br />

lists).<br />

Directory Permissions<br />

Access permissions for directories have the type d. For directories, the individual<br />

permissions have a slightly different meaning.<br />

Example 3.2 Sample Output Showing Directory Permissions<br />

drwxrwxr-x 1 tux project3 35 Jun 21 15:15 ProjectData<br />

In Example 3.2, “Sample Output Showing Directory Permissions” (page 104), the<br />

owner (tux) and the owning group (project3) <strong>of</strong> the directory ProjectData<br />

are easy to recognize. In contrast to the file access permissions from File Access<br />

(page 103), the set reading permission (r) means that the contents <strong>of</strong> the directory<br />

can be shown. The write permission (w) means that new files can be created. The<br />

executable permission (x) means that the user can change to this directory. In the<br />

above example, the user tux as well as the members <strong>of</strong> the group project3 can<br />

change to the ProjectData directory (x), view the contents (r), and add or<br />

delete files (w). The rest <strong>of</strong> the users, on the other hand, are given less access. They<br />

may enter the directory (x) and browse through it (r), but not insert any new files<br />

(w).

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!