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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" }

move you up one directory quickly
In bash, this turns on auto cd. If a command is just a directory name, it cd's into that directory.

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Vectorize xkcd strips
Uses ImageMagick and potrace to vectorize the input image, with parameters optimized for xkcd-like pictures.

Copy an element from the previous command
You can specify a range via '-'.

Identify all amazon cloudformation scripts recursively using ripgrep
This assumes you are in the cwd of where you put your s3 scripts. Its useful if someone decides to create aws cloudformation scripts and doesn't add the 'yaml' or .yml extension.

Hardlink all identical files in the current directory (regain some disk space)
Meaning of switches (see man page too): v verbose p ignore mode (permissions) o ignore owner, group t ignore time of modification Disadvantage: If you modify any linked file, this will propagate to all other files which occupy the same space.

Retrieve the size of a file on a server
- Where $URL is the URL of the file. - Replace the $2 by $3 at the end to get a human-readable size. Credits to svanberg @ ArchLinux forums for original idea. Edit: Replaced command with better version by FRUiT. (removed unnecessary grep)

Rip DVD to YouTube ready MPEG-4 AVI file using mencoder
Rip DVD to YouTube ready AVI file, using MPEG-4 video codec and MP3 audio codec. Resizes to 320x240 and deinterlaces as needed.

Terminal Escape Code Zen - Strace and Tput
Depending on the TERM, the terminfo version, ncurses version, etc.. you may be using a varied assortment of terminal escape codes. With this command you can easily find out exactly what is going on.. This is terminal escape zen! $ ( 2>&2 strace -f -F -e write -s 1000 sh -c 'echo -e "initc\nis2\ncnorm\nrmso\nsgr0" | tput -S' 2>&1 ) | grep -o '"\\[^"]*"' --color=always "\33]4;%p1%d;rgb:%p2%{255}%*%{1000}%/%2.2X/%p3%{255}%*%{1000}%/%2.2X/%p4%{255}%*%{1000}%/%2.2X\33\\\33[!p\33[?3;4l\33[4l\33>\33[?12l\33[?25h\33[27m\33(B\33[m" Lets say you want to find out what you need to echo in order to get the text to blink.. $ echo -e "`tput blink`This will blink`tput sgr0` This wont" Now you can use this function instead of calling tput (tput is much smarter for portable code because it works differently depending on the current TERM, and tput -T anyterm works too.) to turn that echo into a much faster executing code. tput queries files, opens files, etc.. but echo is very strait and narrow. So now you can do this: $ echo -e "\33[5mThis will blink\33(B\33[m This wont" More at http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html


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