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If you apply a DataStage fix pack that contains a new version of osh, you must make provisions to restore the symbolic link which invokes osh-dmotherwise the patch may replace the symlink with a new version of osh. As discussed in the “See also” topics How do we safely update DataStage where the MettleCI Unit Test Harness has been Installed?, the easiest way to do this is run the harness uninstaller prior to applying the patch. Harness installation is reversible and uninstallation will restore the directory structure to the non-symbolically linked version. This uninstall process performs the same set of checks as the install process to ensure it doesn't do anything destructive.
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