Linux Quota Inconsistency Problems

In our system, we use linux quota to limit users file usage. However, quota database has inconsistencies with file usage of users. Sometimes user has no data, however quota database shows 4KB of usage.

On this problem, quotacheck is recommended. However, quotacheck fully checks the disk. If there are too many files and users, also user files frequently changing; online mode of quotacheck can’t fix inconsistencies.


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Linux Process Invisibility

Hello again, we have given a project in System Programming course. It was expected you to alter the kernel code for process invisibility, when you ps, process can not be seen in the output, if process invisibility flag is “1”.

The project was modifying the linux kernel for process invisibility, writing a system call for setting the invisibility flag and writing a user-space program.

Project was developed at Xubuntu 9.10 guest on Windows 7 host. Eclipse (with CDT and Remote System Explorer plugins) was the development IDE. Putty SSH client was also used for executing commands and “command copy/paste” availability. VirtualBox was the virtual machine supervisor.

ATTENTION: This code is experimental. If you try, it will be your own responsibility.
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