Aug 132014
 

Article by giannis_tsakiris first posted on http://www.giannistsakiris.com

A hard link is actually nothing more than a regular directory entry, which in turn can be seen as a pointer to the actual file’s data on the disk. The cool thing about hard-links is that a file can be stored once on the disk, and be linked to multiple times, from different locations/entries, without requiring to allocate extra disk space for each file instance.

But then a question arises: Given a specific file on disk, how can someone know whether it is linked to by other directory entries or not? This can be easily answered using the ls command:

giannis@zandloper:/etc$ ls -l passwd
-rw-r--r-- 1 root root 1402 2008-03-30 17:49 passwd
;

Do you ever wonder what is this small number between the file permissions and the owner in the output of ls’s long listing format (its value is usually “1″ for files, or “2″ for directories)? This number is actually the link-count of the file, when referring to a file, or the number of contained directory entries, when referring to a directory (including the . and .. entries).
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Jun 162014
 

Tee

The command “tee” it’s one of the basic commands that you should find in any system, yet it’s not so popular or use, this command reads standard input and writes it to both standard output and one or more files, effectively duplicating its input. It is primarily used in conjunction with pipes and filters. The command is named after the T-splitter used in plumbing.

In short if you want to redirect the STDOUT of any command as well as printing it to the screen, tee is the right tool to use, let’s see some practical use of this command.
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Feb 192014
 

Original article by http://blog.shineservers.com/

Sometime a process “hang” both if you are using Gnu/Linux on your desktop (maybe a game ?) or as server, in these cases the best thing to do it’s to terminate that process, that probably is using precious resources, the basic commands to do this from a terminal are kill and killall.

killall is a tool for ending running processes on your system based on name. In contrast, kill terminates processes based on process ID number or “PID.” kill and killallcan also send specific system signals to processes. Use killall and kill in conjunction with tools including ps to manage processes and end processes that have become stuck or unresponsive when necessary.

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Linux Terminal: How to color the output in bash scripts

An old article by Todd Partridge (Gently) but still really useful if you are writing some bash scripts and want them more readable with some colors: Users who have been using Linux for awhile often learn that creating a basic script is a good way to run multiple, often-repeated commands. Adding a little color to [...]

Dynamic DNS with Bash & Afraid.org

Recently I’ve published an article about “DynDNS and ddclient: access your Linux from anywhere“, and some people commented that the services on DynDNS are not free anymore, so this is an alternative by Adam Buchanan first published on his interesting blog — This has nothing to do with search engine marketing, but everything to do with [...]