Installation manual

F
NEW_OVER and NEW_UNDER Files
This appendix lists files installed either over or under existing files during an
upgrade.
F.1 Where Files Are Installed
During an upgrade, the procedure replaces certain files that exist on your system
with new versions of those files from the OpenVMS VAX distribution kit. For
some system files, the upgrade procedure does not replace your existing system
files, which might contain customizations for your site. Instead, the procedure
retains your existing file and installs the new file from the kit at a version
number higher or at a version number lower than your existing file.
You can use the DCL command DIFFERENCES to compare the contents of your
existing files and the contents of the new files provided by OpenVMS VAX Version
7.3. Enter the command using the following syntax:
DIFFERENCES/OUTPUT=filespec existing_filename new_filename
The /OUTPUT qualifier causes the DIFFERENCES command to write the list of
differences to the output file you specify. This output file has the default file type
.DIF. For more information about using the DIFFERENCES command, refer to
the OpenVMS DCL Dictionary.
New files that the procedure installs at a version number higher than your
existing files are referred to as new_over files. You must use these files at least
until you complete the upgrade. After you have upgraded your system, you can
add your customizations to these files.
New files installed at a version number lower than the existing files are referred
to as new_under files. This allows you to continue to use your existing files
during and after the upgrade.
If you purge a new_over file, you are left with the new version of the file provided
by the distribution kit, and any customizations you made to the existing file are
lost. If you purge a new_under file, you are left with the file that existed before
the upgrade.
In addition to the new_over and new_under files, there are certain files that are
intended to contain your site-specific modifications. During an upgrade, the old
versions of these files are retained if they were present before the upgrade. The
new version of the file is installed only if no old version is present on your system.
With the exception of TFF$STARTUP.COM, there is a corresponding .TEMPLATE
file for each of the site-specfic files. The new version of the .TEMPLATE file
replaces the old version.
NEW_OVER and NEW_UNDER Files F–1