We’ve compiled a list of six Unix/Linux tools that are cool and useful. From checking the weather via your terminal to having a sysadmin walk you through a difficult task. Interestingly, most of these tools were released decades ago! Read on…

kibitz

kibitz is a terminal tool that can be used by a mentor to assist his or her apprentice. It essentially makes what is normally one private terminal session visible to both parties providing bi-directional interactivity. The mentor can then walk the apprentice through various tasks and howtos. A typical session looks like the following to the mentor:

Whatever commands or text that the mentor or the apprentice types is seen on the other end. It looks like this to the apprentice:

tload

tload is a neat tool that displays the load average on the terminal in a form of character drawings. It gives an interesting visual of the system load (/proc/loadavg) over time – time being an adjustable parameter. Without further ado, here’s a screen shot of tload in action:

catchsegv

catchsegv helps one diagnose programs that segfault. If you’re dealing with an app that segfaults frequently, start it up with catchsegv and watch it produce a snapshot of CPU registers, memory maps, and backtrace at the time of the segfault! Here’s a snapshot of it in action:

dislocate

For those of you who are familiar with the program screen, dislocate is its grandfather.It’s neat tool that allows one to detach programs from the pseudo terminal and reattach to them whenever needed. This is tool for those with slow or unstable terminal sessions that are prone to disconnect.

tac

tac is a command line tool that reads a file in reverse order. It’s ideal for log sifting tasks where one’s interest is in grep’ing the most recent entries.

# cat /var/log/sip Target 1… DONE

Target 2… DONE

Target 3… DONE

# tac /var/log/sip

Target 3… DONE

Target 2… DONE

Target 1… DONE

weather

weather is an expect-based program that runs from the terminal and grabs weather information from rainmaker.wunderground.com. Wunderground runs a public weather service on port 3000. weather leverages this service to pull weather data by city and displays it on the terminal. Here’s a sample run:

$ weather HOU <snip> Enter 3-letter city code: HOU Weather Conditions at 12:53 PM CST on 24 Dec 2010 for Houston Intercontinental, TX. Temp(F) Humidity(%) Wind(mph) Pressure(in) Weather ======================================================================== 63 70% ESE at 10 30.07 Overcast Forecast for Houston, TX 406 am CST Fri Dec 24 2010 .Today…Mostly cloudy with a 30 percent chance of showers. Highs in the upper 60s. Southeast winds 10 to 15 mph. .Tonight…Showers likely and isolated thunderstorms. Lows in the mid 40s. Northeast winds 5 to 10 mph in the evening becoming north and increasing to 15 to 20 mph after midnight. Chance of rain 70 percent in the evening decreasing to 60 percent after <snip>

That’s all folks! I hope you enjoyed this entry.