Commands by Dentorman (5)

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list block devices
Shows all block devices in a tree with descruptions of what they are.

processes per user counter
use Linux ;)

Console clock -- within screen
Configures screen to always display the clock in the last line (has to be configured only once). After that you not only have got the possibility to detach sessions and run them in background, but also have got a nice clock permanently on your screen.

Delete line number 10 from file
Very useful when the ssh key of a host has changed and ssh refuses to connect to the machine, while giving you the line number that has changed in ~/.ssh/known_hosts.

Quickly create an alias for changing into the current directory
Put the function in your .bashrc and use "map [alias]" to create the alias you want. Just be careful to not override an existing alias.

Update all ant packages installed in gentoo
Update all "ant" packages installed on Gentoo

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

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" }

Number of CPU's in a system
/proc/cpuinfo contains information about the CPU. Search for "processor" in the /proc/cpuinfo file wc -l, counts the number of lines.

du with colored bar graph
i'm using gawk, you may get varying mileage with other varieties. You might want to change the / after du to say, /home/ or /var or something, otherwise this command might take quite some time to complete. Sorry it's so obsfucated, I had to turn a script into a one-liner under 255 characters for commandlinefu. Note: the bar ratio is relative, so the highest ratio of the total disk, "anchors" the rest of the graph. EDIT: the math was slightly wrong, fixed it. Also, made it compliant with older versions of df.

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