UNDELETE is a utility that can be used to recover deleted disk files. Recovering deleted disk files is not a sure thing. When a file is deleted, its disk space is freed for use by newly created files. In general, the sooner after deletion you attempt to recover files, the greater is your likelihood of success. WARNING!!! Follow these directions carefully. This procedure can totally demolish your disk structure if not used properly! Make sure you understand what is being done in this procedure, especially with regard to the DEC utility VFY. UNDELETE attempts to resurrect disk files that have been accidently deleted. Files to be recovered are specified using a search pattern similar to the SRD Select Entry option: 1. A question mark or asterisk will match any single character; 2. Stem searches are performed for the file name and type fields; and 3. Any unspecified fields default to a wild card search. The special version numbers, 0 and -1, are not supported. Whenever a matched file header is found, its file ID is printed, along with a PIP-like listing of the file owner, file specification, size and creation date. This information will be helpful in returning the file to the proper directory (usually the owner's UFD). The procedure to follow is: 1. Log on to a privileged account, preferably on a hardcopy terminal. 2. Immediately halt all activity on the disk and DMOunt it. 3. ALLocate the disk to yourself and MOUnt it with the index file unlocked (/UNL). 4. Run UNDELETE and provide the name of the disk and the search pattern ( RUN $UNDELETE ) 5. Run VFY (/UP and /LO options) with the listing and scratch files directed to another disk. (The listing file may get rather lengthy if lots of disk blocks were deleted, so you may want to send the listing to a disk or NL:.) (VFY requires that the UIC [1, 3] be present on the disk being recovered. UNDELETE will prompt you with the command lines to use for VFY when UNDELETE completes step 4.) 6. Rename the recovered files from [1,3] to their proper directories. (Warning: recover all files before renaming, or copy them to another medium one directory at a time. If you guess wrong at the proper UFD, it could be extended to accommodate the new directory entries and re-use a disk block from one of the files yet to be recovered.) 7. If there are extra recovered files that you want to delete again, be sure to rebuild the volume bit map again to take care of doubly allocated disk blocks before returning it to service (the /RE and /UP options in VFY). 8. Always VFY the disk one last time before putting it back on-line! 9. When you're satisfied everything is OK, return the disk back to its original state (PUBLIC, /-UNL, etc.).