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stl_scp(4) Kernel Interfaces Manual stl_scp(4) NAME
stl_scp - Subset control program conventions for the setld utility DESCRIPTION
Each software subset that is distributed for the setld(8) command can have an associated subset control program. These programs perform the application-specific management operations that configure the subset into the system. Because subset control programs must be executed during installation to non-native file hierarchies, they must be written in an architecture-neutral language. Because these programs may also be required to run while the system is in the single-user run state, the interpreter must not use shared libraries. The use of /sbin/sh is strongly recommended. As subsets are installed and deleted, they pass through several system management states. Software is in the NEW state immediately after being extracted from the distribution media and verified. Software in this state is exactly as it was prepared for distribution by the software vendor. The subset control program is responsible for placing the software in the PROTOTYPE state at the request of setld. Software in this state is configured for use at a particular site. All of the software remains sharable but has undergone some level of customization. Software becomes runnable on a particular system and ceases to be sharable after it has been placed in the CONFIGURED state by the subset control program, again at the request of setld. Subset control programs are executed by setld to perform specific requested operations. Before executing a subset control program, setld sets the environment variable ACT to an action value. The subset control program is expected to inspect this variable and any command-line arguments to determine which actions to perform. The action values, the command-line arguments, and the behavior that setld expects are as follows: Configure subset The first command-line argument is a configuration message for the subset. The subset control program can interpret this message as it chooses. There are two reserved subset messages: Perform any management operations required to change the subset from the PROTO- TYPE state to the CONFIGURED state. Subset control programs called to perform this action must assume that the /usr file system is write locked and that the currently visible execution context (contents of /dev/kmem and so forth) is the same as that in which the application will execute. Perform any management operations required to change the subset from the CONFIGURED state to the PROTO- TYPE state. The execution environment is identical to that for C, INSTALL. Menu Request The first argument is one of -l or -x and specifies whether the user is installing or extracting software from the media. Determine if the subset is suitable for presentation to the user in the subset selection menu. If the subset is to be presented, the subset control program should return exit status 0. If the subset is not to be presented, the subset control program should return a nonzero status. Prepare for Deletion The subset is about to be deleted from the system. Perform any management operations required to change the subset from the PROTO- TYPE state to the NEW state. A nonzero return status can be returned to indicate that the subset should not be deleted. Prepare for Load The subset is about to be loaded onto the system. Verify that the system is ready for the subset to loaded from the installation media. A nonzero exit status can be returned to indicate that the subset should not be installed. Post Deletion Cleanup The subset control program should perform any management operations required to return the system to the state that it was in prior to installation of the subset. Post Load Configuration The subset has been loaded from the media and is on the system in the NEW state. The subset control program must change the subset from the NEW state to the PROTOTYPE state. Verify Subset The setld utility checks for the existence of the installed subset. If the subset exists, the setld utility verifies the size and checksum information for each file in the subset. If the subset control program includes any V phase processing, it is executed at this time. The setld utility does not execute subset control processing during the installation process. RELATED INFORMATION
setld(8) Guide to Preparing Product Kits delim off stl_scp(4)
