05-04-2013
Point: With modern hardware a "raw disc" can be multiple physical discs which the Operating System sees as one physical disc.
Some research ideas:
Consider the case of a virgin disc. There are no filesystems unless your software creates a filesystem. You can write or read whatever you like within the physical dimensions of the disc.
The very basic filesystems follow the pattern of the original IBM tape format VOL1 HDR1.
For research purposes it is worth a look at CAFS (Content Addressable File Store). That's the way to use a raw disc! It's so much better than "Binary Tree", "Hash Random" or "Index Sequential" file systems when dealing with disorganised data.
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LEARN ABOUT ULTRIX
quotacheck
quotacheck(8) System Manager's Manual quotacheck(8)
Name
quotacheck - file system quota consistency checker
Syntax
/etc/quotacheck [ -v ] [ -f ] filesystem ...
/etc/quotacheck [ -v ] -a
Description
The command examines each file system, builds a table of current disc usage, and compares this table against that stored in the disc quota
file for the file system. If detects any inconsistencies, it updates both the quota file and the current system copies of the incorrect
quotas. Inconsistencies occur only if an active file system is checked.
Normally, returns a warning if it cannot find a valid quota file. If you use the option, creates a quota file automatically and then per-
forms its normal functions.
If you use the flag in place of any file system name, checks all the file systems listed in to be read-write with disc quotas.
Normally reports only modified quotas. If the option is supplied, will indicate the calculated disc quotas for each user on a particular
file system.
The command expects each file system to be checked to have a quota file named in the root directory. If none is present, will ignore the
file system.
The command is normally run at boot time from the file, before enabling disc quotas with For further information, see
The command accesses the raw device in calculating the actual disc usage for each user. Thus, the file systems checked should be quiescent
while is running.
Files
Default file systems
See Also
quota(2), setquota(2), quotaon(8)
``Disk Quotas in a UNIX Environment,'' ULTRIX Supplementary Documents, Volume 3: System Manager
quotacheck(8)