Linux CLI Talk

The first talk of the new year 2007 got off to a flying start.

Abrar Kazi was the speaker. He was in his full elements.

Abrar started by giving an overview of the shell interface and its various components.

He explained how the interpreter works, argument collection and then went on discuss many scripts in detail.

For those of us starting anew, an Open Source system like Linux or FreeBSD work through the various run levels with the help of multitudinous scripts (rc scripts)

A particularly useful place to look on your Linux system is /etc/init.d/ directory which contains a lot of scripts. Studying the scripts provides a good understanding of the various constructs (if, do, while, case, shift args) in terms of their usage.

One of the very important aspect of script development is intermediate state analysis and debugging.

'set -x -v'
'bash -xv'
are your friends while doing active script development.

Abrar illustrated a lot of interesting aspects related to
/etc/profile
su, su -, sudo, /etc/sudoers
variable scope in scripts
arith eval, $(( )), expr
sed
awk
sh
tr
awk -F
seq first last
seq last inc first

The discussion about Regular Expressions (reg ex) in the context of shell scripting and PCRE was very enlightening. The differences between grep, egrep, fgrep were very useful.

Knowledge of Regular expressions is very useful in the case of URL re-writing (mod_rewrite) as in path munging for creating clean URLs and redirected downloads on websites.

Editor architecture, key mapping and usage technique was another very interesting area of discussion.
ex
ed
sed
vi
vim
emacs
xemacs
were discussed.

Once a user understands the architecture and process model, using the editor can boost the productivity multiple times.

Many a member in the audience had a smile as they saw that the discussion addressed many of their outstanding queries.

Abrar is a very persuasive speaker whose Knowledge base span is very wide. You can see all Linux HOWTO filling up his laptop. There are all sorts of Open Source software on his laptop.

The two much deserved breaks in this intense and invigorating talk were fully utilized to catch up with friends and colleagues.

The free coffee from Cafe Coffee Day and Badam Milk added warmth to the bonhomie.

Mr. Kishore, who is a Ajax expert was seen yesterday after a long period of recovery from an unfortunate accident. We wish him good health in the coming year. Kishore is also mentoring a
TWINCLING Society member, Raghava, on a project.

As is customary in all TWINCLING Society Meets, many photos were taken and the group photo session was held at 9pm. The photos will be uploaded on the new website that will be
released shortly.

Thanks to all the patrons, members and well wishers of the Society who made it to the meet !

Thank you and have a great weekend.

sincerely
TWINCLING Society News and Editorial Team (TSNET)