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Group membership in OS X is a mish-mash of standards that end up meaning there's almost a half-dozen of ways to belong to a group, what with group inheritance and automatic assignment. This means there's no easy command to find out all groups a user belongs to. The only sensible way then is to list all users and then query each user for membership.
NOTE: This is a function. Once input you can execute it by calling with a groupname.
This takes a webcam picture every everytime the mouse is moved (waits 10 seconds between checking for movement) and stores the picture wherever you want it.
Ideas:
Use in conjunction with a dropbox type application to see who is using your computer
Use /dev/input/mice if /dev/input/mouse* doesn't work
Use the bones of this to make a simple screensaver
List background jobs, grep their number - not process id - and then kill them
proc lister
usage: p
proc killer
usage: p patt [signal]
uses only ps, grep, sed, printf and kill
no need for pgrep/pkill (not part of early UNIX)
_p(){
ps ax \
|grep $1 \
|sed '
/grep.'"$1"'/d' \
|while read a;do
printf ${a%% *}' ';
printf "${a#* }" >&2;
printf '\n';
done;
}
p(){
case $# in
0)
ps ax |grep .|less -iE;
;;
1)
_p $1;
;;
[23])
_p $1 2>/dev/null \
|sed '/'"$2"'/!d;
s,.*,kill -'"${3-15}"' &,'|sh -v
;;
esac;
}
alas, can't get this under 255 chars.
flatcap?
proc lister
usage: p
proc killer
usage: p patt [signal]
uses only ps, grep, sed, printf and kill
no need for pgrep/pkill (not part of early UNIX)
_p(){
ps ax \
|grep $1 \
|sed '
/grep.'"$1"'/d' \
|while read a;do
printf ${a%% *}' ';
printf "${a#* }" >&2;
printf '\n';
done;
}
p(){
case $# in
0)
ps ax |grep .|less -iE;
;;
1)
_p $1;
;;
[23])
_p $1 2>/dev/null \
|sed '/'"$2"'/!d;
s,.*,kill -'"${3-15}"' &,'|sh -v
;;
esac;
}
alas, can't get this under 255 chars.
flatcap?
Emulate (more or less) Git equivalent of
git log --format='tformat:%h %an (%cr) %s'
This command find which of your zip (or jar) files (when you have lots of them) contains a file you're searching for. It's useful when you have a lot of zip (or jar) files and need to know in which of them the file is archived.
It's most common with .jar files when you have to know which of the .jar files contains the java class you need.
To find in jar files, you must change "zip" to "jar" in the "find" command. The [internal file name] must be changed to the file name you're searching that is archived into one of the zip/jar files.
Before run this command you must step into the directory that contains the zip or jar files.
I can't find the lid command on my system, there is also another complied program: http://xyne.archlinux.ca/projects/lsgrp/
The script gets the dimensions and position of a window and calls ffmpeg to record audio and video of that window. It saves it to a file named output.mkv
Bash only, no sed, no awk. Multiple spaces/tabs if exists INSIDE the line will be preserved. Empty lines stay intact, except they will be cleaned from spaces and tabs if any available.
Kills all the threads from the user provided in the WHERE request.
Can be refined through the SQL request, of course, see http://dev.mysql.com/doc/refman/5.1/en/processlist-table.html for the available columns.
Certain Flash video players (e.g. Youtube) write their video streams to disk in /tmp/ , but the files are unlinked. i.e. the player creates the file and then immediately deletes the filename (unlinking files in this way makes it hard to find them, and/or ensures their cleanup if the browser or plugin should crash etc.) But as long as the flash plugin's process runs, a file descriptor remains in its /proc/ hierarchy, from which we (and the player) still have access to the file. The method above worked nicely for me when I had 50 tabs open with Youtube videos and didn't want to have to re-download them all with some tool.
Very useful for test a script. After launch this command, you only have to press ENTER for launch your script again. I work with screen and tape ENTER instead of '!!'+ENTER
If you break your script with CTRL-C, it will wait for press ENTER and will re-launch
You can write like it : while read -p "Press ENTER" ; do python ; done
I have used single packet, and in a silent mode with no display of ping stats. This is with color and UI improvement to the http://www.commandlinefu.com/commands/view/10220/check-if-a-machine-is-online. It is as per the enhancements suggested.
full command:
for fn in xkcd*.png xkcd*.jpg; do; echo $fn; read xw xh <<<$(identify -format '%w %h' $fn); nn="$(echo $fn | sed 's/xkcd-\([0-9]\+\)-.*/\1/')"; wget -q -O xkcd-${nn}.json http://xkcd.com/$nn/info.0.json; tt="$(sed 's/.*"title": "\([^"]*\)", .*/\1/' xkcd-${nn}.json)"; at="$(sed 's/.*alt": "\(.*\)", .*/\1/' xkcd-${nn}.json)"; convert -background white -fill black -font /usr/share/fonts/truetype/freefont/FreeSansBold.ttf -pointsize 26 -size ${xw}x -gravity Center caption:"$tt" tt.png; convert -background '#FFF9BD' -border 1x1 -bordercolor black -fill black -font /usr/share/fonts/truetype/freefont/FreeSans.ttf -pointsize 16 -size $(($xw - 2))x -gravity Center caption:"$at" at.png; th=$(identify -format '%h' tt.png); ah=$(identify -format '%h' at.png); convert -size ${xw}x$(($xh+$th+$ah+5)) "xc:white" tt.png -geometry +0+0 -composite $fn -geometry +0+$th -composite at.png -geometry +0+$(($th+$xh+5)) -composite ${fn%\.*}_cmp.png; echo -e "$fn $nn $xw $xh $th $ah \n$tt \n$at\n"; done
this assumes that all comics are saved as xkcd-[number]-[title].{png|jpg}.
it will then download the title and alt-text, create pictures from them, and put everything together in a new png-file.
it's not perfect, but it worked for nearly all my comics.
it uses the xkcd-json-interface.
though it's poorly written, it doesn't completely break on http://xkcd.com/859/