Technical data

Customizing the Operating System
5.4 Customizing Startup Databases with SYSMAN
To enable a previously disabled file, enter the STARTUP ENABLE FILE
command in the following format:
STARTUP ENABLE FILE filespec
where filespec specifies the name of the file to be enabled.
Example
$ RUN SYS$SYSTEM:SYSMAN
SYSMAN> STARTUP ENABLE FILE FOR$LPMAIN_043_STARTUP.COM/NODE=ZURICH
5.5 Registering Images that Have System Version Dependencies
Applications that run on the OpenVMS operating system sometimes depend
on the internal interfaces of a previous version of the operating system. For
example, an application might call system routines, reference system data cells,
or system data structures. New versions of the operating system might include
changes that can break applications depending on those interfaces.
Registering an image records information about the image in a file called the
image registry. The image activator, INSTALL, and SYSGEN do not check
the versions of images that are recorded in the image registry. Image registry
allows you to continue to run application images (including main images, shared
libraries, and device drivers) that depend on the internal interfaces of a previous
version of the operating system.
The Image Registry facility allows you to register different versions of an image
independently. It also allows you to deregister, analyze, and show images in the
image registry.
5.5.1 Understanding System Version Dependency and the Image Registry
Applications that depend on internal interfaces are bound to a particular version
of the operating system when the application is linked. Version-dependent images
reference both of the following version numbers:
• The major version number of the operating system
• A set of component version numbers (version numbers of loadable executive
images)
Images can be linked against SYS.STB in one of two ways:
Images linked against SYS.STB with the Linker utility qualifier
/SELECTIVE_SEARCH include component version numbers only for those
symbols that were referenced at link time. (This is the recommended
method.)
Images linked against SYS.STB without the /SELECTIVE_SEARCH
qualifier include references to all component versions.
When you attempt to run an image, the system checks to determine if the image
requires a certain version of the operating system or of system components. If
the version of the running system does not match the version requirements of the
image, the image fails.
The system also checks version numbers when you attempt to install an image
using the Install utility (INSTALL) or connect a device driver using the System
Generation utility (SYSGEN).
Customizing the Operating System 5–23