Differences

This shows you the differences between two versions of the page.

--- mkatari-bioinformatics-august-2013-introlinuxnotes [2015/06/11 09:11] – [File manipulation] mkatari
+++ mkatari-bioinformatics-august-2013-introlinuxnotes [2015/06/11 09:19] – [File manipulation] mkatari
@@ Line 189: / Line 189: @@
 </code>
+====== Permissions ======
+There are three levels of permissions that can be assigned to all files, programs, and directories
+  * Read: open the file and copy it
+  * Write: edit the file and delete it
+  * Execute: Run the commands in the file or change into the directory if it is a directory
+There are also three different levels of users:
+  * User – you
+  * Group – A collection of users that are in a group
+  * Everyone - Not just the people who have accounts on the machine but if the directory is open to the public and any one.
+The commands used to change owner, group, and specific permissions are:
+  * chown – changes the owner
+  * chgrp – changes the group
+  * chmod – change read, write, and execute permissions
+    * +/- r = read
+    * +/- w = write
+    * +/- x = execute
+    * u = user level
+    * g = group level
+    * o = others
+    * a = all
+  * chmod can also use three numbers to set permissions where the value of the number represents a specific combination of rwx and their order assigns it to the different levels (u,g,o)