Linux Know-How: Exercises

These are some practical examples where awk can be useful.

For the first exercise, your input is lines in the following form:
Username:Firstname:Lastname:Telephone number
Make an awk script that will convert such a line to an LDAP record in this format:
dn: uid=Username, dc=example, dc=com cn: Firstname Lastname sn: Lastname telephoneNumber: Telephone number
Create a file containing a couple of test records and check.
Create a Bash script using awk and standard UNIX commands that will show the top three users of disk space in the /home file system (if you don't have the directory holding the homes on a separate partition, make the script for the / partition; this is present on every UNIX system). First, execute the commands from the command line. Then put them in a script. The script should create sensible output (sensible as in readable by the boss). If everything proves to work, have the script email its results to you (use for instance mail -s Disk space usage <you@your_comp> < result).

If the quota daemon is running, use that information; if not, use find.

Create XML-style output from a Tab-separated list in the following form:

Meaning very long line with a lot of description

meaning another long line

othermeaning    more longline

testmeaning     looooooooooooooooooooooong line, but i mean really looooooooooooooooooooooong.

The output should read:

<row>
<entry>Meaning</entry>
<entry>
very long line
</entry>
</row>
<row>
<entry>meaning</entry>
<entry>
long line
</entry>
</row>
<row>
<entryothermeaning</entry>
<entry>
more longline
</entry>
</row>
<row>
<entrytestmeaning</entry>
<entry>
looooooooooooooooooooooong line, but i mean really looooooooooooooooooooooong.
</entry>
</row>

Additionally, if you know anything about XML, write a BEGIN and END script to complete the table. Or do it in HTML.

Exercises - Gawk