Commands by seb1245 (10)

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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.

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Search commandlinefu from the command line
There's probably a more efficient way to do this rather than the relatively long perl program, but perl is my hammer, so text processing looks like a nail. This is of course a lot to type all at once. You can make it better by putting this somewhere: $ clf () { (curl -d "[email protected]" http://www.commandlinefu.com/search/autocomplete 2>/dev/null) | egrep 'autocomplete|votes|destination' | perl -pi -e 's/$/\n\n/g;s/^ +|\([0-9]+ votes,//g;s/^\//http:\/\/commandlinefu.com\//g'; } Then, to look up any command, you can do this: $ clf diff This is similar to http://www.colivre.coop.br/Aurium/CLFUSearch except that it's just one line, so more in the spirit of CLF, in my opinion.

Start a terminal with three open tabs
If you launch gnome-terminal manually, you can start with three open tabs

list your device drivers
great for running off a bootable cd to identify hardware other os's can't detect

ARP Scan
A much quicker and (not dirtier) option. use the man page for help. On linux/ubuntu you will need to `sudo apt-get -y install arp-scan`.

Averaging columns of numbers
This example calculates the averages of column one and column two of "file.dat". It can be easily modified if other columns are to be averaged.

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" }

Limit the transfer rate and size of data over a pipe
This example will close the pipe after transferring 100MB at a speed of 3MB per second.

list files recursively by size

Find usb device
I often use it to find recently added ou removed device, or using find in /dev, or anything similar. Just run the command, plug the device, and wait to see him and only him

Use jq to validate and pretty-print json output
The `jq` tool can also be used do validate json files and pretty print output: ` jq < file.json` Available on several platforms, including newer debian-based systems via `#sudo apt install jq`, mac via `brew install jq`, and from source https://stedolan.github.io/jq/download/ This alternative to the original avoids the useless use of cat


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Follow the Tweets.

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