howto:find_the_filename_when_all_you_have_is_the_file_id
Information
There are occasions where you have a File_ID of a file, but not the name. Probably related to $ ANALYZE/DISK errors such as this one:
%ANALDISK-W-MULTALLOC, file (3224,22,0) multiply allocated blocks VBN 37225 to 37227 LBN 6934554 to 6934556, RVN 1
So how do you determine the name of the file in question?
Procedure
Create a command procedure with the following information:
$! fid_header_dump.com $ if p1 .eqs. "" then inquire p1 "Disk name" $ if p1 .eqs. "" then exit $ if p2 .eqs. "" then inquire p2 "File ID" $ p2 = p2 - "(" - ")" $ if p2 .eqs. "" then exit $! $ show symbol p1 $ p1 = p1 - ":" + ":" $ disk = f$parse (p1,,,"device") $ show symbol disk $ fid = f$element (0, ",", p2) $! $ cluster = f$getdvi (disk, "cluster") $ maxfil = f$getdvi (disk, "maxfiles") $ bitmap = (maxfil + 4095) / 4096 $ skip = cluster * 4 + bitmap $ block = skip + fid $ dump /file_header 'disk'[000000]indexf.sys /block=(s:'block',c:1)
Example usage:
For this example, the ANALYZE/DISK command was on disk DSA2, so that is provided into the command.
$ @fid_header_dump dsa2 "(3224,22,0)" P1 = "DSA2" DISK = "DSA2:" Dump of file DSA2:[000000]INDEXF.SYS;1 on 1-FEB-2019 11:58:20.28 File ID (1,1,0) End of file block 471860 / Allocated 471888 Virtual block number 3921 (00000F51), 512 (0200) bytes Header area Identification area offset: 40 Map area offset: 100 Access control area offset: 255 Reserved area offset: 255 Extension segment number: 0 Structure level and version: 2, 1 File identification: (3224,22,0) Extension file identification: (0,0,0) VAX-11 RMS attributes Record type: Variable File organization: Sequential Record attributes: Implied carriage control Record size: 18 Highest block: 144 End of file block: 1 End of file byte: 38 Bucket size: 0 Fixed control area size: 0 Maximum record size: 255 Default extension size: 0 Global buffer count: 0 Directory version limit: 0 File characteristics: <none specified> Caching attribute: Writethrough Map area words in use: 3 Access mode: 0 File owner UIC: [STAFF,MMACGREGOR] File protection: S:RWED, O:RWED, G:RE, W: Back link file identification: (2091,15,0) Journal control flags: <none specified> Active recovery units: None File entry linkcount: 0 Highest block written: 1 Client attributes: None Identification area File name: LOGIN.COM;1 <<<< FILENAME DISPLAYED HERE Revision number: 2 Creation date: 1-FEB-2019 11:53:13.36 Revision date: 1-FEB-2019 11:53:13.42 Expiration date: <none specified> Backup date: <none specified> Map area Retrieval pointers Count: 144 LBN: 16220592 Checksum: 10562
howto/find_the_filename_when_all_you_have_is_the_file_id.txt · Last modified: 2019/02/01 19:20 by mmacgregor