Changes

==Heyu==

==Heyu Overview==

{{Level|Medium}}

{{Level|Medium}}

Initiated: [[User:Christian | Christian]] - created initial procedure and initiated wiki entry

Initiated: [[User:Christian | Christian]] - created initial procedure and initiated wiki entry

===Obtaining the software===

===Obtaining the software===

The software is available only in source form from:

The software is available only in source form from:

  heyu monitor

  heyu monitor

===Use via another application===

==Use via another application==

====Overview====

===Overview===

As given in the references, heyu is often used by higher level applications such as web application. In this case, it should be noted that the application's identity will be passed to heyu and thus certain resources may not be accessible to the application. For example, the serial port (e.g. ttyS5) normally has the ownership of user=root,group=uucp, and permission 0660. Normally heyu can access this because it runs as root.

As given in the references, heyu is often used by higher level applications such as web application. In this case, it should be noted that the application's identity will be passed to heyu and thus certain resources may not be accessible to the application. For example, the serial port (e.g. ttyS5) normally has the ownership of user=root,group=uucp, and permission 0660. Normally heyu can access this because it runs as root.

If however you have a web application it may be running as www hence would not be able to have heyu access the serial port. Group membership or memberships can be adjusted as needed with consideration to the security implications.  

If however you have a web application it may be running as www hence would not be able to have heyu access the serial port. Group membership or memberships can be adjusted as needed with consideration to the security implications.  

====Changing permission on serial port====

===Changing permission on serial port===

In the case of the serial port, you could either modify its ownership or its permissions. In this example, we will allow others to have read/write permission specifically on the serial port of interest (e.g. ttyS5). By default udev only allows user and group with read/write and other has no access.

In the case of the serial port, you could either modify its ownership or its permissions. In this example, we will allow others to have read/write permission specifically on the serial port of interest (e.g. ttyS5). By default udev only allows user and group with read/write and other has no access.

After reboot verify that only your serial port has been changed.

After reboot verify that only your serial port has been changed.

=====Special notes=====

====Special notes====

Udev follows permission rules in the order in which they appear. So the serial port rule is named to preceed the default set of permissions (hence 41 at the beginning of the file).

Udev follows permission rules in the order in which they appear. So the serial port rule is named to preceed the default set of permissions (hence 41 at the beginning of the file).

This procedure works for CentOS 4 (SME 7) but will change in CentOS 5 (SME 8) to use rules.d instead.

This procedure works for CentOS 4 (SME 7) but will change in CentOS 5 (SME 8) to use rules.d instead.

===Documentation===

===Documentation===

Heyu is very well documented and includes man pages. Start with:

Heyu is very well documented and includes man pages. Start with: