system administration

One problem with using the truncate operator for string matching is case matching.

In the truncate operator example, ${foo%%*ATE} matches SENATE.


DALEK$ foo=SENATE
DALEK$ if [ '' = "${foo%%*ATE}" ] ; then echo "$foo! $foo!"; fi
SENATE! SENATE!
DALEK$


It will not match Senate because ate and ATE are different cases.


DALEK$ foo=Senate
DALEK$ if [ '' = "${foo%%*ATE}" ] ; then echo "$foo! $foo!"; fi
DALEK$


While creating materials for my bash class I needed to create some globbing exercises for my students.

It occurred to me that a string operator and a comparison to the null string can be used to check if something is a substring of another value.

Sure, you can use Substring Expansion to see if the substring is at a known location such as "Does the value of $foo start with 'bar'?", but length and location are often unknown.


$ foo=barfood
$ if [ 'bar' = "${foo:0:3}" ]; then echo $foo; fi
barfood
$


LibrePlanet, the Free Software Foundation's annual technology conference, was a great experience in March.

The conference started with a fantastic keynote from Deb Nicholson, "Free software forever."

Topics: Firejail, AppArmor and SELinux

In October Aaron will be teaching us about locking down processes via three diff
erent mechanisms.

• Firejail: sandbox to restrict the application environment
• AppArmor: a Mandatory Access Control system, common for debian based distros
• SELinux: a Mandatory Access Control system, common for Red Hat based distros

The PLUG security meeting is a monthly open entry security class ( 3rd Thursday ).

Free Software Stammtisch job networking event this Tuesday at 18:00.

We encourage engineers from groups that are hiring and hiring managers to attend. The goal is for prospective candidates to learn about the company and the actual job while giving the team a chance to meet prospective candidates. Interviews are bi-directional, so are job searches.

We have several confirmed employers this month: