Editing Chmod (section)

==Examples==
<!-- Please keep meaningful names and use examples that someone might want. DGerman
And remember: less is more. KISS -->

Add '''w'''rite permission to the '''g'''roup class of a directory, allowing users in the same group to add files:

<syntaxhighlight lang="console" highlight="3">
$ ls -ld dir # before
drwxr-xr-x   2 jsmitt  northregion 96 Apr 8 12:53 shared_dir
$ chmod g+w dir
$ ls -ld dir  # after
drwxrwxr-x   2 jsmitt  northregion 96 Apr 8 12:53 shared_dir
</syntaxhighlight>

Remove '''w'''rite permission for '''a'''ll classes, preventing anyone from writing to the file:

<syntaxhighlight lang="console" highlight="3">
$ ls -l ourBestReferenceFile
-rw-rw-r--   2 tmiller  northregion 96 Apr 8 12:53 ourBestReferenceFile
$ chmod a-w ourBestReferenceFile
$ ls -l ourBestReferenceFile
-r--r--r--   2 tmiller  northregion 96 Apr 8 12:53 ourBestReferenceFile
</syntaxhighlight>

Set the permissions for the '''u'''ser and '''g'''roup classes to '''r'''ead and e'''x'''ecute only; no '''w'''rite permission; preventing anyone from adding files:

<syntaxhighlight lang="console" highlight="3">
$ ls -ld referenceLib
drwxr-----   2 ebowman  northregion 96 Apr 8 12:53 referenceLib
$ chmod ug=rx referenceLib
$ ls -ld referenceLib
dr-xr-x---   2 ebowman  northregion 96 Apr 8 12:53 referenceLib
</syntaxhighlight>

Enable '''w'''rite for the '''u'''ser class while making it '''r'''ead-only for '''g'''roup and others:

<syntaxhighlight lang="console">
$ chmod u=rw,go=r sample
$ ls -ld sample
drw-r--r--   2 oschultz  warehousing       96 Dec  8 12:53 sample
</syntaxhighlight>

To recursively set access for the directory '''docs/''' and its contained files:

<code>chmod -R u+w docs/</code>

To set user and group for read and write only and set others for read only:

<code>chmod 664 file</code>

To set user for read, write, and execute only and group and others for read only:

<code>chmod 744 file</code>

To set the sticky bit in addition to user, group and others permissions:

<code>chmod 1755 file</code>

To set UID in addition to user, group and others permissions:

<code>chmod 4755 file</code>

To set GID in addition to user, group and others permissions:

<code>chmod 2755 file</code>