42  * Recovery code.
45  * paths of a b+tree file and a mail recovery file.  The former is the file
48  * simple states of recovery are:
51  *		the b+tree file exists and is mode 700, the mail recovery
54  *		the b+tree file exists and is mode 600, the mail recovery
58  * file descriptor for the mail recovery file.
60  * To find out if a recovery file/backing file pair are in use, try to get
61  * a lock on the recovery file.
72  * haven't yet failed at setting up or doing recovery.
74  * To preserve a recovery file/backing file pair, set the F_RCV_NORM bit.
82  * file.  When the file is first modified, the mail recovery file is created,
89  * The recovery mail file contains normal mail headers, with two additional
95  * Btree files are named "vi.XXXXXX" and recovery files are named
110  *	Build a file name that will be used as the recovery file.
126 	 * If the recovery directory doesn't exist, try and create it.  As  in rcv_tmp()
127 	 * the recovery files are themselves protected from reading/writing  in rcv_tmp()
129 	 * would have permission to remove other user's recovery files.  If  in rcv_tmp()
166  *	Force the file to be snapshotted for recovery.
200 		    "057|Copying file for recovery...", BUSY_ON);  in rcv_init()
265 	 * the recovery information, i.e. it's like the user re-edited the  in rcv_sync()
267 	 * recovery file, it's simpler than exiting and reopening all of the  in rcv_sync()
286 		    "061|Copying file for recovery...", BUSY_ON);  in rcv_sync()
369 		msgq(sp, M_SYSERR, "063|Unable to lock recovery file");  in rcv_mailfile()
401 	    "From: root@", host, " (Nvi recovery program)",  in rcv_mailfile()
418 	    host, ", when it was saved for recovery. ",  in rcv_mailfile()
472 werr:		msgq(sp, M_SYSERR, "065|Recovery file");  in rcv_mailfile()
507 	/* Open the recovery directory for reading. */  in rcv_list()
530 			 * should permit recovery anyway.  If this is wrong,  in rcv_list()
549 					    "066|%s: malformed recovery file");  in rcv_list()
563 		 * If the file doesn't exist, it's an orphaned recovery file,  in rcv_list()
645 			 * should permit recovery anyway.  If this is wrong,
666 					    "067|%s: malformed recovery file");
681 		 * If the file doesn't exist, it's an orphaned recovery file,
784  *	Copy a recovery file.