Commands by tjcertified (1)

  • This command lists extended information about files, i.e. whether or not it is a true file or link, who owns it, etc. without having to 'ls' from the specific directory. If you know the filename, but not the location, this helps with finding other information about the file. It can be truncated by creating an alias for 'ls -l'. The sample output shows difference in regular locate vs. ls + locate. Show Sample Output


    -5
    ls -l `locate your_search_here`
    tjcertified · 2009-11-27 05:53:46 3

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands


Check These Out

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Empty a file
Immediately make a file empty. This even works if the file is still being written to. Great for cleaning up huge log files!

Listing today’s files only

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Stripping ^M at end of each line for files
just deletes to rogue CR from dos files, and tr is always available.

Get the IP of the host your coming from when logged in remotely
Even faster without the need for cut... :)

Do one ping to a URL, I use this in a MRTG gauge graph to monitor connectivity

ROT13 using the tr command

Sort a character string
Sorts a character string, using common shell commands.

Find the real procesor speed when you use CPU scaling [cpuspeed]
We don't use CPU scaling, but just in case you do, there is something interesting to note. If you look at the /proc/cpuinfo, the speed listed is current running speed of the processors and not the real speed of the chip.


Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: