Commands by Paaskehare (6)

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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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List last opened tabs in firefox browser

Pause Current Thread
Hold ctrl and press z to pause the current thread. Run $fg to resume it.

Delete all but the latest 5 files, ignoring directories

Backup your hard drive with dd
This will create an exact duplicate image of your hard drive that you can then restore by simply reversing the "if" & "of" locations. $ sudo dd if=/media/disk/backup/sda.backup of=/dev/sda Alternatively, you can use an SSH connection to do your backups: $dd if=/dev/sda | ssh user@ssh.server.com dd of=~/backup/sda.backup

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" }

Turn white color to transparent for a series of png images
mogrify can be used like convert. The difference is that mogrify overwrites files: http://www.imagemagick.org/www/mogrify.html Of course, other source colors can be used as well.

HTTP redirect
any HTTP requests to the machine on the specified port will be redirected to http://www.whatevs.com... quick, dirty, works fine for sites w/

Route outbound SMTP connections through a addtional IP address rather than your primary

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Strace all signals processes based on a name ( The processes already started... ) with bash built-in
Especially for sysadmins when they don't want to waste time to add -p flag on the N processes of a processname. In the old school, you did ; $ pgrep processname and typing strace -f -p 456 -p 678 -p 974... You can add -f argument to the function. That way, the function will deal with pgrep to match the command-line. Example : $ processname -f jrockit

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