Sponsored Content
Top Forums UNIX for Advanced & Expert Users Cannot find logical file format for BSD file headers. Post 302957124 by Chris_top_he_r on Wednesday 7th of October 2015 09:35:19 AM
Old 10-07-2015
Hammer & Screwdriver Cannot find logical file format for BSD file headers.

Hi. Unix rookie here. Been looking for a few days for reference documents on how BSD UNIX lays the logical file format onto a disk. Goal is to view/edit with hex editor for data repair. Lots of docs are available for how to use Unix commands (like xxd), but I want to learn the map of how Unix stores the file header and file data and cluster information on the hard disk. I've asked on a few forums and emailed companies (like R-tt regarding R-Studio for Mac) and have no answer yet. Anyone know where I can read about this?
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Help with find command and list in a long format each found file

The purpose of those comands are to find the newest file in a directory acvrdind to system date, and it has to be recursively found in each directory. The problem is that i want to list in a long format every found file, but the commands i use produce unexpected results ,so the output lists in a... (5 Replies)
Discussion started by: alexcol
5 Replies

2. UNIX for Dummies Questions & Answers

Option in sql script to include column headers when spooling file to .csv format

Can anyone help me how to include COLUMN HEADER when spooling file to .CSV format through SQL statement. Thanks, Akbar (4 Replies)
Discussion started by: s1a2m3
4 Replies

3. Shell Programming and Scripting

Merging of files with different headers to make combined headers file

Hi , I have a typical situation. I have 4 files and with different headers (number of headers is varible ). I need to make such a merged file which will have headers combined from all files (comman coluns should appear once only). For example - File 1 H1|H2|H3|H4 11|12|13|14 21|22|23|23... (1 Reply)
Discussion started by: marut_ashu
1 Replies

4. Shell Programming and Scripting

How to check for file name of specific format using find?

I have to find the specific formatted file is present in the received list in the directory, for which I have written: file_list=`ls -lrt /tmp/vinay/act/files |grep "$cdate"| awk '{print $9}'` while read fileStr do find $file_list $fileStr > /dev/null status=`echo $?` if ; then ... (3 Replies)
Discussion started by: IND123
3 Replies

5. Shell Programming and Scripting

Find first created file date in YYYYMMDD format

Hi All, We are copying all the files into ARCHIVE directory after we process them. We are doing this process from last 2 years, now we have a lot of files in ARCHIVE directory. Now I need to find when the first file is copied into this directory? If I Issue, ls -l /ARCHIVE/*.* | tail -1... (3 Replies)
Discussion started by: Raamc
3 Replies

6. Shell Programming and Scripting

Find files older than X with a weird file format

I have an issue with a korn shell script that I am writing. The script parses through a configuration file which lists a heap of path/directories for some files which need to be FTP'd. Now the script needs to check whether there are any files which have not been processed and are X minutes old. ... (2 Replies)
Discussion started by: MickAAA
2 Replies

7. Shell Programming and Scripting

Multiple headers in a file

Hi , I have a .txt file in which I have multiple headers, the header record starts with $ symbol...like the first column name is $Account. I have to keep the header in the first line and delete all the remaining headers which are in the file. I tried using sort adc.txt | uniq -u , but my... (7 Replies)
Discussion started by: gaur.deepti
7 Replies

8. Shell Programming and Scripting

Merging File with headers

Hi I need to merge 4 files. The issue i am facing is all the files have headers and i do not want them in the final output file. Can anybody suggest how to do it? (5 Replies)
Discussion started by: Arun Mishra
5 Replies

9. UNIX for Dummies Questions & Answers

Append file name to fasta file headers in Linux

How do we append the file name to fasta file headers in multiple fasta-files in Linux? (10 Replies)
Discussion started by: Mauve
10 Replies

10. Shell Programming and Scripting

How to find list of missing files based on the file format?

Hi All, In the file names we have dates. Based on the file format given by the user, if any file is not existed for a particular date with in a given interval we should consider that file is missing. I have the below files in the directory /bin/daily/voda_files. ... (9 Replies)
Discussion started by: nalu
9 Replies
addbadsec(1M)						  System Administration Commands					     addbadsec(1M)

NAME
addbadsec - map out defective disk blocks SYNOPSIS
addbadsec [-p] [ -a blkno [blkno...]] [-f filename] raw_device DESCRIPTION
addbadsec is used by the system administrator to map out bad disk blocks. Normally, these blocks are identified during surface analysis, but occasionally the disk subsystem reports unrecoverable data errors indicating a bad block. A block number reported in this way can be fed directly into addbadsec, and the block will be remapped. addbadsec will first attempt hardware remapping. This is supported on SCSI drives and takes place at the disk hardware level. If the target is an IDE drive, then software remapping is used. In order for software remapping to succeed, the partition must contain an alternate slice and there must be room in this slice to perform the mapping. It should be understood that bad blocks lead to data loss. Remapping a defective block does not repair a damaged file. If a bad block occurs to a disk-resident file system structure such as a superblock, the entire slice might have to be recovered from a backup. OPTIONS
The following options are supported: -a Adds the specified blocks to the hardware or software map. If more than one block number is specified, the entire list should be quoted and block numbers should be separated by white space. -f Adds the specified blocks to the hardware or software map. The bad blocks are listed, one per line, in the specified file. -p Causes addbadsec to print the current software map. The output shows the defective block and the assigned alternate. This option cannot be used to print the hardware map. OPERANDS
The following operand is supported: raw_device The address of the disk drive (see FILES). FILES
The raw device should be /dev/rdsk/c?[t?]d?p0. See disks(1M) for an explanation of SCSI and IDE device naming conventions. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Architecture |x86 | +-----------------------------+-----------------------------+ |Availability |SUNWcsu | +-----------------------------+-----------------------------+ SEE ALSO
disks(1M), diskscan(1M), fdisk(1M), fmthard(1M), format(1M), attributes(5) NOTES
The format(1M) utility is available to format, label, analyze, and repair SCSI disks. This utility is included with the addbadsec, diskscan(1M), fdisk(1M), and fmthard(1M) commands available for x86. To format an IDE disk, use the DOS "format" utility; however, to label, analyze, or repair IDE disks on x86 systems, use the Solaris format(1M) utility. SunOS 5.10 24 Feb 1998 addbadsec(1M)
All times are GMT -4. The time now is 04:44 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy