Commands by eightmillion (20)

  • This command outputs a table of sighting opportunities for the International Space Station. Find the URL for your city here: http://spaceflight.nasa.gov/realdata/sightings/ Show Sample Output


    5
    links -dump "http://spaceflight.nasa.gov/realdata/sightings/cities/view.cgi?country=United_States&region=Wisconsin&city=Portage" | sed -n '/--/,/--/p'
    eightmillion · 2011-05-03 12:15:56 3
  • This uses Perl's rename utility (you may have to call it as prename on your box) and won't choke on spaces or other characters in filenames. It will also zero pad a number even in filenames like "vacation-4.jpg".


    12
    rename 's/\d+/sprintf("%04d",$&)/e' *.jpg
    eightmillion · 2011-05-01 20:50:36 5
  • This command finds and prints all the symbolic and hard links to a file. Note that the file argument itself be a link and it will find the original file as well. You can also do this with the inode number for a file or directory by first using stat or ls or some other tool to get the number like so: stat -Lc %i file or ls -Hid file And then using: find -L / -inum INODE_NUMBER -exec ls -ld {} +


    17
    find -L / -samefile /path/to/file -exec ls -ld {} +
    eightmillion · 2011-04-27 06:14:15 4
  • This function is used to set environmental variables from a list of alternatives depending on what's installed on the system. It returns the first program found in the list. Example usage: export BROWSER=$(find_alternatives chromium-browser google-chrome opera firefox firefox-bin iceweasel konqueror w3m lynx) . export EDITOR=$(find_alternatives vim nano pico emacs kate) . export PAGER=$(find_alternatives vimpager less most more pg)


    -1
    find_alternatives(){ for i;do which "$i" >/dev/null && { echo "$i"; return 0;};done;return 1;}
    eightmillion · 2011-01-06 19:53:46 1
  • Ruby version. Also, a perl version: perl -e 'printf("%.2x.",rand(255))for(1..5);printf("%.2x\n",rand(255))'


    3
    ruby -e 'puts (1..6).map{"%0.2X"%rand(256)}.join(":")'
    eightmillion · 2010-12-08 10:01:31 5
  • This command turns a multi-line file into a single line joined with <SOMETEXT>. To skip blank lines, use: perl -pe '(eof()||s/^\s*$//)||s/\n/<SOMETEXT>/g' file.txt Show Sample Output


    3
    perl -pe 'eof()||s/\n/<SOMETEXT>/g' file.txt
    eightmillion · 2010-12-02 01:19:27 3
  • I took matthewbauer's cool one-liner and rewrote it as a shell function that returns all the suggestions or outputs "OK" if it doesn't find anything wrong. It should work on ksh, zsh, and bash. Users that don't have tee can leave that part off like this: spellcheck(){ typeset y=$@;curl -sd "<spellrequest><text>$y</text></spellrequest>" https://google.com/tbproxy/spell|sed -n '/s="[1-9]"/{s/<[^>]*>/ /g;s/\t/ /g;s/ *\(.*\)/Suggestions: \1\n/g;p}';} Show Sample Output


    6
    spellcheck(){ typeset y=$@;curl -sd "<spellrequest><text>$y</text></spellrequest>" https://www.google.com/tbproxy/spell|sed -n '/s="[0-9]"/{s/<[^>]*>/ /g;s/\t/ /g;s/ *\(.*\)/Suggestions: \1\n/g;p}'|tee >(grep -Eq '.*'||echo -e "OK");}
    eightmillion · 2010-02-17 08:20:48 13
  • I use this alias in my bashrc. The --vi-keys option makes info use vi-like and less-like key bindings.


    4
    alias info='info --vi-keys'
    eightmillion · 2010-02-16 16:35:17 2
  • Converts reserved characters in a URI to their percent encoded counterparts. Alternate python version: echo "$url" | python -c 'import sys,urllib;print urllib.quote(sys.stdin.read().strip())' Show Sample Output


    7
    echo "$url" | perl -MURI::Escape -ne 'chomp;print uri_escape($_),"\n"'
    eightmillion · 2010-02-13 00:44:48 15
  • This shell function grabs the weather forecast for the next 24 to 48 hours from weatherunderground.com. Replace <YOURZIPORLOCATION> with your zip code or your "city, state" or "city, country", then calling the function without any arguments returns the weather for that location. Calling the function with a zip code or place name as an argument returns the weather for that location instead of your default. To add a bit of color formatting to the output, use the following instead: weather(){ curl -s "http://api.wunderground.com/auto/wui/geo/ForecastXML/index.xml?query=${@:-<YOURZIPORLOCATION>}"|perl -ne '/<title>([^<]+)/&&printf "\x1B[0;34m%s\x1B[0m: ",$1;/<fcttext>([^<]+)/&&print $1,"\n"';} Requires: perl, curl Show Sample Output


    7
    weather(){ curl -s "http://api.wunderground.com/auto/wui/geo/ForecastXML/index.xml?query=${@:-<YOURZIPORLOCATION>}"|perl -ne '/<title>([^<]+)/&&printf "%s: ",$1;/<fcttext>([^<]+)/&&print $1,"\n"';}
    eightmillion · 2010-02-10 01:23:39 9
  • This function takes a word or a phrase as arguments and then fetches definitions using Google's "define" syntax. The "nl" and perl portion isn't strictly necessary. It just makes the output a bit more readable, but this also works: define(){ local y="$@";curl -sA"Opera" "http://www.google.com/search?q=define:${y// /+}"|grep -Po '(?<=<li>)[^<]+';} If your version of grep doesn't have perl compatible regex support, then you can use this version: define(){ local y="$@";curl -sA"Opera" "http://www.google.com/search?q=define:${y// /+}"|grep -Eo '<li>[^<]+'|sed 's/<li>//g'|nl|perl -MHTML::Entities -pe 'decode_entities($_)' 2>/dev/null;} Show Sample Output


    18
    define(){ local y="$@";curl -sA"Opera" "http://www.google.com/search?q=define:${y// /+}"|grep -Po '(?<=<li>)[^<]+'|nl|perl -MHTML::Entities -pe 'decode_entities($_)' 2>/dev/null;}
    eightmillion · 2010-01-29 05:01:11 9
  • This is a command that I find myself using all the time. It works like regular grep, but returns the paragraph containing the search pattern instead of just the line. It operates on files or standard input. grepp <PATTERN> <FILE> or <SOMECOMMAND> | grepp <PATTERN> Show Sample Output


    13
    grepp() { [ $# -eq 1 ] && perl -00ne "print if /$1/i" || perl -00ne "print if /$1/i" < "$2";}
    eightmillion · 2010-01-12 04:30:15 8
  • This command, taken from play's manual page, plays a synthesized guitar tone for each of the strings on a standard tuned guitar. The command "play" is a part of the package "sox".


    17
    for n in E2 A2 D3 G3 B3 E4;do play -n synth 4 pluck $n repeat 2;done
    eightmillion · 2009-12-13 06:57:26 11
  • This function displays the latest comic from xkcd.com. One of the best things about xkcd is the title text when you hover over the comic, so this function also displays that after you close the comic. To get a random xkcd comic, I also use the following: xkcdrandom(){ wget -qO- dynamic.xkcd.com/comic/random|tee >(feh $(grep -Po '(?<=")http://imgs[^/]+/comics/[^"]+\.\w{3}'))|grep -Po '(?<=(\w{3})" title=").*(?=" alt)';}


    24
    xkcd(){ wget -qO- http://xkcd.com/|tee >(feh $(grep -Po '(?<=")http://imgs[^/]+/comics/[^"]+\.\w{3}'))|grep -Po '(?<=(\w{3})" title=").*(?=" alt)';}
    eightmillion · 2009-11-27 09:11:47 16
  • This uses mpg123 to convert the files to wav before burning, but you can use mplayer or mencoder or ffmpeg or lame with the --decode option, or whatever you like.


    3
    alias burnaudiocd='mkdir ./temp && for i in *.[Mm][Pp]3;do mpg123 -w "./temp/${i%%.*}.wav" "$i";done;cdrecord -pad ./temp/* && rm -r ./temp'
    eightmillion · 2009-11-21 19:57:18 1
  • Substitute feh for the image viewer of your choice. display (part of imagemagick) seems to be a popular choice.


    3
    apod(){ local x=http://antwrp.gsfc.nasa.gov/apod/;feh $x$(curl -s ${x}astropix.html|grep -Pom1 'image/\d+/.*\.\w+');}
    eightmillion · 2009-11-18 12:06:03 5
  • This bash function uses albumart.org to find the cover for an album. It returns an amazon.com url to the image. Usage: albumart [artist] [album] These arguments can be reversed and if the album name is distinct enough, it may be possible to omit the artist. The command can be extended with wget to automatically download the matching image like this: albumart(){ local x y="$@";x=$(awk '/View larger image/{gsub(/^.*largeImagePopup\(.|., .*$/,"");print;exit}' <(curl -s 'http://www.albumart.org/index.php?srchkey='${y// /+}'&itempage=1&newsearch=1&searchindex=Music'));[ -z "$x" ]&&echo "Not found."||wget "$x" -O "${y}.${x##*.}";} Show Sample Output


    7
    albumart(){ local y="$@";awk '/View larger image/{gsub(/^.*largeImagePopup\(.|., .*$/,"");print;exit}' <(curl -s 'http://www.albumart.org/index.php?srchkey='${y// /+}'&itempage=1&newsearch=1&searchindex=Music');}
    eightmillion · 2009-11-15 19:54:16 3
  • This command lets you select from 10 different BBC stations. When one is chosen, it streams it with mplayer. Requires: mplayer with wma support.


    23
    bbcradio() { local s PS3="Select a station: ";select s in 1 1x 2 3 4 5 6 7 "Asian Network an" "Nations & Local lcl";do break;done;s=($s);mplayer -playlist "http://www.bbc.co.uk/radio/listen/live/r"${s[@]: -1}".asx";}
    eightmillion · 2009-11-14 08:17:03 19
  • This function uploads images to http://omploader.org and then prints out the links to the file. Some coloring can also be added to the command with: ompload() { curl -F file1=@"$1" http://omploader.org/upload|awk '/Info:|File:|Thumbnail:|BBCode:/{gsub(/<[^<]*?\/?>/,"");$1=$1;sub(/^/,"\033[0;34m");sub(/:/,"\033[0m:");print}';} Show Sample Output


    8
    ompload() { curl -# -F file1=@"$1" http://ompldr.org/upload|awk '/Info:|File:|Thumbnail:|BBCode:/{gsub(/<[^<]*?\/?>/,"");$1=$1;print}';}
    eightmillion · 2009-11-07 20:56:52 2
  • This is a kind of wrapper around the shell builtin cd that allows a person to quickly go up several directories. Instead of typing: cd ../.. A user can type: cd ... Instead of: cd ../../.. Type: cd .... Add another period and it goes up four levels. Adding more periods will take you up more levels.


    5
    cd() { if [[ "$1" =~ ^\.\.+$ ]];then local a dir;a=${#1};while [ $a -ne 1 ];do dir=${dir}"../";((a--));done;builtin cd $dir;else builtin cd "$@";fi ;}
    eightmillion · 2009-10-29 21:43:51 5

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Ensure that each machine that you log in to has its own history file
On systems where your home directory is shared across different machines, your bash history will be global, rather than being a separate history per machine. This setting in your .bashrc file will ensure that each machine has its own history file.

Every Nth line position # (AWK)
A better way to show the file lines 3n + 1

list ips with high number of connections

Leap year calculation

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" }

Easily find latex package documentation
If the pdf/dvi/etc documentation for a latex package is already part of your local texmf tree, then texdoc will find and display it for you. If the documentation is not available on your system, it will bring up the package's webpage at CTAN to help you investigate.

extract column from csv file
extracts the 5th column using the delimiter ','

Get a quick list of all user and group owners of files and dirs under the cwd.
find -printf '%u\n' | sort | uniq #just users find -printf '%g\n' | sort | uniq #just groups

check open ports (both ipv4 and ipv6)

Update your journal
prerequisite: $ mkdir ~/journal


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