Commands by alecnmk (1)

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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" }

find files beginning with filename* that do not include "string"
Inverse grep, to find files without the string

open path with your default program (on Linux/*BSD)
open [path] in the default program, regardless of which Desktop Environment you use (KDE, GNOME, etc.) Works on all "freedesktop.org" compatible desktop environments

Move mp3 files to another path with existing subtree structure
Use case: folder with flac files with tree structure ../artist/album/number-title.flac 1) convert flac->mp3 in the same folder: http://www.commandlinefu.com/commands/view/6341/convert-all-.flac-from-a-folder-subtree-in-192kb-mp3 2) search for mp3 files and recreate tree structure to another path: http://www.commandlinefu.com/commands/view/8853/copy-selected-folder-found-recursively-under-src-retaining-the-structure 3) move all mp3 files to that new folder: this command

Mnemonic for `nice` and `renice` command
This is just a phrase I use to help me remember which way is what when using nice (top, renice, etc.), and not a command, (unless you really want this in your .bash_history to help remind you.) I was using the command `man nice ` way too much just to look up which way is what. This saves 9 keystrokes every time I remember it. Make sure you downvote me if you think mnemonics sux. Otherwise I hope this helps someone else.

Open a Remote Desktop (RDP) session with a custom resolution.
Using a widescreen monitor, I often get annoyed that the RDP window is too high, or too narrow for what I want to display. In this example, I'm on a 1680 x 1050 display.

swap stdout and stderr
Possible use, to filter something in stderr: (/usr/bin/$COMMAND $PARAM 3>&1 1>&2 2>&3 | grep -v $uninteresting_error ) 3>&1 1>&2 2>&3

Secure copy from one server to another without rsync and preserve users, etc
Source: http://unix.derkeiler.com/Newsgroups/comp.unix.shell/2008-04/msg00068.html

Generate an XKCD #936 style 4 word password
4 random words are better than one obfuscated word http://xkcd.com/936/

Make sudo forget password instantly
By default sudo 'remembers' password for a few minutes, so that you do not need to re-enter password for a series of sudo commands that might follow within a short time duration. However, sometime you might want sudo to instantly 'forget' the password. (Next sudo command will need you to reenter the password) Credit: I first learned this while listening to one of the 'tuxradar' podcast.


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