Commands by MrMerry (3)

What's this? 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

Clear current session history (bash)

Matrix Style
Unlike other alternatives, this command only relies on bash builtins and should also work on windows platforms with the bash executable. Sparseness corresponds to the number 128 and can be adjusted. To print all possible digits instead of only 0 and 1 replace RANDOM%2 by RANDOM%10 or RANDOM%16 to add letters [A-F].

Create a PNG screenshot of Rigol Ultravision scopes attached per LAN
Scope should have the Rigol Ultravision Technology otherwise it won't accept the command. ImageMagic is required. Scope sends a 1.1M BMP file and converted to PNG it's only 18-20K

Use colordiff in side-by-side mode, and with automatic column widths.
Barely worth posting because it is so simple, but I use it literally all the time. I was always frustrated by the limitations that a non-gui environment imposes on diff'ing files. This fixes some of those limitations by colourising the output (you'll have to install colordiff, but it is just a wrapper for diff itself), using side-by-side mode for clearer presentation, and of course, the -W parameter, using tput to automatically insert you terminal width. Note that the double quotes aren't necessary if typed into terminal as-is. I included them for safety sake,

Translates a phrase from English to Portuguese
Translates a string from English to Portuguese by using google translator web service.

Find default gateway (proper at ppp connections too)

list with full path

List top ten files/directories sorted by size

convert single digit to double digits
each number in a file name gets expanded to the number of digets provided as arg_1 of the arguments in rjust_file_nums. Put the funciton in the .bashrc file. Be sure to $ source ~/.bashrc so that the function will be accessible from bash.

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" }

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.


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: