Interesting Unix commands

if you are looking to change/solve a problem and

have no idea what command to use (an extreme situation)

man -k whatever

might come handy

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A script that telnet and submits a password

ina very NON secure way

echo "password" | telnet machine

in certain situations where u r telneting dumb machines

ina local network that have default passwords that can be handy

a better but more complex approach is using "expect"

Scheduling jobs on OSX

Hello,

While MacOSX is bsd based, coming from a unix/linux background you would automatically look

for cron to schedule your jobs and maintenance scripts.

However, MacOSX adopted launchd as a replacement for many tools including

init, rc, the init.d and rc.d scripts, SystemStarter (Mac OS X),inetd and xinetd, atd, crond and watchdogd (http://en.wikipedia.org/wiki/Launchd).

After a bad experience with cron on MacOSX in which I configured a job to run at 14

* 14 * * * * /myscript and instead of running once at 14 the script kept running and running

what definitely lead to other problems and server load averages increasing dramatically.

the trick was that I had to specify the minute of hour, so the line in crontab -e would look

0 14 * * * * /myscript, that ran the script once properly.

A more neat and Macky way to do it is using launchctl, a tool that makes things easy

is lingon by Peter Borg http://lingon.sourceforge.net/.

.... to be continued