The /etc/system file is read once while the kernel is booting. It is used to set various kernel options. After this file is modified, the system must be rebooted for the changes to take effect. If a change in the file causes the system not to work, boot with the ask (-a) option and specify /dev/null as the system file.
Add the following set commands to the /etc/system file:
To set module variables, specify the module name and the variable:
set module_name:variable=value
To set the variable xxdebug in driver xx, use the following set command:
set xx:xxdebug=1
To set a kernel integer variable, omit the module name. Other assignments are also supported, such as bitwise OR'ing a value into an existing value:
set moddebug | 0x80000000
See system(4) for more information.
Most kernel variables are not guaranteed to be present in subsequent releases.