…with an open minded approach


modprobe resume

modprobe, used in all linuxes


modprobe lsmod resume

modprobe lsmod resume


You can link or copy it, if you mention the author/source 🙂

dpkg resume

dpkg, used in debian/ubuntu systems underneath APT

You can copy or link it if you mention the author 🙂

Yum resume

Without any further delay, here it goes


yum resume

yum resume


You can link or copy it, as long as you mention the author 🙂

Not complete, but it’s a good introduction to the main pieces


Drop a comment if you like it 🙂

Bash initialization files

This bash resume diagram is respectfully copied from http://www.solipsys.co.uk/new/BashInitialisationFiles.html

I’ll post it here before I need it again – its just great

RPM resume diagram

I’ve been reading a bit to take the LPIC-1 certificate – thought it was about time to get some official certificate stating that “all those hours around linux were not about playing games, it made you really learn somethings very usefull”. I already knew it, but the certificate is the most forefront way to show it to other people, and so here we go 🙂

The LPIC-1 seems quite accessible although you do need to read it over and study the details specific for the exam… the interesting content seems to be in LPIC-2 where the administration goes into more interesting services…

Well, the thing is I’ve taken my notes and made this resume-diagram, so I though better to share – here it goes


Not going to rewrite the excellent resumes that can be found in internet (such as http://bobcares.com/blog/rpm-basics/) so straight to the point – the resume diagram.

This resume is only about RPM, not including YUM (RPM is like Debian’s DPKG, while YUM is like Debian’s APT) and is saved as a SVG file and uploaded into a public github-repo so you can easily edit/improve/correct it – If you do so, drop a comment, it cheers up 🙂

Unfortunately WordPress does not allow to post SVG images (?!?) , so I’ve linked to a PNG version (its on github) – hope its usefull to you

RPM resume diagram

Sed info

Sed – An Introduction and Tutorial by Bruce Barnett – I really should post this up before I forget: it’s a sed resume that goes from-basic-to-deep features, progressively explaining what-does-what with examples… a really good reference for sed usage


If you’r into sed, take a look – it will be worth it


bash ternary-like comparisons…

Bash does not have a ternary operator ?: to do things like ” condition ? command-if-true : command-if-false ”

Its possible to do the same with “if”s but its not so neat and compact…

One hacky alternative which is possible in bash, is to do ” condition && command-if-true || command-if-false”, like so:

Hope it helps – if so drop a comment

bash trap and signals (or how to execute something at end of bash script)

In Bash scripts we can use “trap” to define handlers for capturing system-signals.

Apart from capturing system-signals (see a list of them with “kill -l”) bash also attends a non-standard EXIT signal, which is emitted just before the bash program exits.

In overall, being able to define handler for signals may be handy for example to grab “CTRL-C” or to clean temp-files before exiting


Running this twice, one first-time hitting CTRL-C and another time waiting untill it finishes, gives



Light overview of unix signals (indicating most common ones), in tutorialspoint

Bash with signals, from Bash Guide for Beginners

LinuxJournal article explaining that EXIT is not a real system-signal, but is synthesized by bash, with a very good overview of it all

find in subdirectories with limited depth

Better take note of this, so next time won’t need to search again for it: how to use find limiting the subdirectories-depth
Use “find –maxdepth <0=no-subdirs,1,2,…>

The info of “man find”, is not very understandable – goes into “find tests” and “arguments”… – so an example was what made it clear for me.

Hope it’s usefull for you too 🙂 – if so, drop a comment, it motivates me 🙂

Ruby: pass file descriptor between processes with unix sockets

The gist is (hopefully) self-explanatory – if not, read the header notes

Long story short – use UNIXSocket.send_io/recv_io to pass a file-descriptor between 2 processes.

Also, learned some Jruby limitations (?bug?):

  • Jruby cannot fork()
  • Jruby has UNIXSocket#send_io/recv_io broken, so its not possible to pass file-descriptors with Jruby… what a pitty…

And learned that working with Unix socket in ruby is soooo easy 🙂

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