A device on a 4.3 BSD system is accessible to an application only when:
A device on an AIX is accessible to an application only when:
The device specific programs called methods, found in the /etc/methods directory, maintain the object database. The methods are invoked by the Configuration Manager (accessed through the cfgmgr command) and other commands.
If a device can no longer be accessed by an application program, it may mean the hardware is faulty or it may mean that the configuration database in the /etc/objrepos directory is damaged.
The cfgmgr command processes the configuration database in the /etc/objrepos directory is processed at startup time by the cfgmgr command (the Configuration Manager).
The pseudocode below shows the Configuration Manager logic:
/* Main */ While there are rules in the Config_Rules database { Get the next rule and execute it Capture stdout from the last execution Parse_Output(stdout) } /* Parse Output Routine */ /* stdout will contain a list of devices found */ Parse_OutPut(stdout) { While there are devices left in the list { Lookup the device in the database if (!defined) Get define method from database and execute if (! configured) { Get config method from database and execute Parse_Output(stdout) } } }