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Working with Configuration Variables

Q: How do I delete an Open Firmware Configuration Variable without having to start the Macintosh computer while depressing cmd-opt-p-r? This method resets all other variables to their defaults while deleting the variable of interest.

A: To delete an individual variable whose name is xyz you must first enter the Open Firmware user interface. You do this as follows:

Start the Macintosh computer while depressing cmd-opt-o-f. At the user interface type:

delenv xyz

In summary there are three commands for working with these variables.

printenv -> will list all variables

setenv name value -> will edit an existing variable whose name is "name" to "value" or create a new variable called "name" if "name" does not already exist and set its value to "value".

delenv name -> will delete "name"

These variables reside in the Open Firmware device tree options node.

[Feb 13 2002]

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