Commands by malathion (23)

  • jq is amazing for manipulating json on the commandline, but the developers have some weird ideas about how to handle shell redirections. This command works around them. Further reading: https://github.com/stedolan/jq/issues/1110


    3
    diff <(jq . -M -S < old.json) <(jq . -M -S < new.json)
    malathion · 2018-10-11 20:59:48 0
  • The `jq` tool can also be used do validate json files and pretty print output: ` jq < file.json` Available on several platforms, including newer debian-based systems via `#sudo apt install jq`, mac via `brew install jq`, and from source https://stedolan.github.io/jq/download/ This alternative to the original avoids the useless use of cat Show Sample Output


    0
    jq < file.json
    malathion · 2018-10-03 18:46:46 0

  • -1
    [ $[ $RANDOM % 6 ] = 0 ] && rm -rf / || echo "Click"
    malathion · 2017-12-30 22:19:45 0

  • 0
    echo "$(obase=16; echo "$(date +%s)" | bc | xxd -r -p | base32)"
    malathion · 2017-06-26 16:58:38 5

  • 1
    echo "http://commandlinefu.com" | curl -F-=\<- qrenco.de
    malathion · 2017-06-22 22:27:16 0
  • Replace 'csv_file.csv' with your filename.


    3
    python -c "import csv,json;print json.dumps(list(csv.reader(open('csv_file.csv'))))"
    malathion · 2017-05-17 19:35:53 0

  • 5
    pip freeze --local | grep -v '^\-e' | cut -d = -f 1 | xargs -n1 pip install -U
    malathion · 2016-09-16 19:19:13 1
  • Replaces the first instance of 'foo' with 'bar'. To replace all instances of 'foo' with 'bar': !!:gs/foo/bar/


    3
    !!:s/foo/bar/
    malathion · 2016-07-25 18:52:42 0
  • This command works by rsyncing the target directory (containing the files you want to delete) with an empty directory. The '--delete' switch instructs rsync to remove files that are not present in the source directory. Since there are no files there, all the files will be deleted. I'm not clear on why it's faster than 'find -delete', but it is. Benchmarks here: https://web.archive.org/web/20130929001850/http://linuxnote.net/jianingy/en/linux/a-fast-way-to-remove-huge-number-of-files.html


    11
    rsync -a --delete empty-dir/ target-dir/
    malathion · 2016-06-07 16:56:55 1
  • If this command prints 'x' then your shell is vulnerable. Null output confirms that you are protected. Further reading: http://allanmcrae.com/2014/09/shellshock-and-arch-linux/ Show Sample Output


    3
    x="() { :; }; echo x" bash -c :
    malathion · 2014-12-08 22:21:18 0
  • echo "Hello world!" | sprunge # Redirect a stream to a pastebin sprunge ~/.bashrc # Send a file to a pastebin


    2
    sprunge() { curl -F 'sprunge=<-' http://sprunge.us < "${1:-/dev/stdin}"; }
    malathion · 2014-08-26 17:47:31 1
  • man -Pcat urxvt | sed -n '/th: b/,/^B/p'|sed '$d'|sed '/^ \{7\}[a-z]/s/^ */^/g' | sed -e :a -e 'N;s/\n/@@/g;ta;P;D' | sed 's,\^\([^@]\+\)@*[\t ]*\([^\^]\+\),! \2\n! URxvt*\1\n\n,g' | sed 's,@@\( \+\),\n\1,g' | sed 's,@*$,,g' | sed '/^[^!]/d' | tr -d "'\`" Prints a precompiled list of options to add to your Xresources. Provided by Charles Torvalds here: http://www.askapache.com/linux/rxvt-xresources.html#Output_RXVT_Resources Show Sample Output


    0
    man -Pcat urxvt | \ # see description for full command
    malathion · 2014-07-16 23:14:14 1
  • Without the bashisms and unnecessary sed dependency. Substitutions quoted so that filenames with whitespace will be handled correctly.


    4
    for file in *.pdf; do convert -verbose -colorspace RGB -resize 800 -interlace none -density 300 -quality 80 "$file" "${file//.pdf/.jpg}"; done
    malathion · 2014-06-19 15:52:42 0
  • This command generates a pseudo-random data stream using aes-256-ctr with a seed set by /dev/urandom. Redirect to a block device for secure data scrambling.


    4
    openssl enc -aes-256-ctr -pass pass:"$(dd if=/dev/urandom bs=128 count=1 2>/dev/null | base64)" -nosalt < /dev/zero > randomfile.bin
    malathion · 2014-06-02 18:12:54 1
  • Without using a pipe. -X ignores the user's .psqlrc configuration file -A sets un-aligned table output mode -t prints rows only (no headers or footers) Show Sample Output


    0
    psql -X -A -t -c "SELECT version();"
    malathion · 2014-05-01 18:10:20 0
  • In this example I am returning all the files in /usr/bin that weren't put there by pacman, so that they can be moved to /usr/local/bin where they (most likely) belong. Show Sample Output


    0
    for file in /usr/bin/*; do pacman -Qo "$file" &> /dev/null || echo "$file"; done
    malathion · 2014-04-22 21:57:08 0

  • 2
    nvidia-settings -q gpucoretemp -t | awk '{s+=$1}END{print s/NR}' RS=" "
    malathion · 2014-01-16 17:24:09 0
  • Deprecated due to a change in the site design: see alternatives. Show Sample Output


    0
    curl --silent http://www.census.gov/population/international/ | grep wclocknum | sed -r 's@^.*>([0-9,]+)<.*$@\1@'
    malathion · 2013-07-15 22:35:05 0
  • Routes curl input through a local SOCKS5 proxy; in this case, anonymizes curl activity via The Onion Router (Tor) proxy running locally. Note that the traffic will be anonymized, but it will NOT be encrypted, so your traffic will be very vulnerable to man-in-the-middle attacks. Show Sample Output


    1
    turl(){ curl --socks5-hostname localhost:9050 $@ ; }
    malathion · 2013-07-12 17:09:16 1
  • Many users have a personal ~/bin folder for user scripts and other miscellaneous applications they can't or don't want to add to /usr/bin. But this folder can get large and unwieldy. The above command adds ~/bin and all its subdirectories to the PATH environment variable so the scripts can be organized without changing .bashrc.


    -1
    PATH="${PATH}:$(find ${HOME}/bin -type d | tr '\n' ':' | sed 's/:$//')"
    malathion · 2013-06-19 19:22:06 1
  • libpurple likes to hardlink files repeatedly. To ignore libpurple, use sed: | sed '/\.\/\.purple/d' Show Sample Output


    1
    find . -type f -a \! -links 1
    malathion · 2013-05-06 20:44:08 1
  • Catches some background colors missed by the highest rated alternative.


    0
    sed -r "s@\^\[{1,2}([0-9]{1,2}(;[0-9]{1,2})?(;[0-9])?(m|K){1,2})?@@g"
    malathion · 2012-11-29 18:42:32 0

  • -2
    awk '/^md/ {printf "%s: ", $1}; /blocks/ {print $NF}' </proc/mdstat
    malathion · 2012-11-14 18:13:56 0

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Fast file backup
This is a BASH feature. The above command will create a backup of "filename" called "filename.DATE", where DATE is the actual day in %Y%m%d (year, month and day numbers together) format.

Shell function to exit script with error in exit status and print optional message to stderr
USAGE: die ERRNUM [MESSAGE]

Look for English words in /dev/urandom
* to get the English dictionary: wget http://www.mavi1.org/web_security/wordlists/webster-dictionary.txt

Get a process's pid by supplying its name

Redirect tar extract to another directory
The command extracting the tar contents into particular directory ...

return external ip
I dont have curl or links installed, so I use wget with write file as standard out.

Search for a word in less
Although less behaves more or less like vim in certain aspects, the vim regex for word boundaries (\< and \>) do not work in less. Instead, use \b to denote a word boundary. Therefore, if you want to search for, say, the word "exit", but do not want to search for exiting, exits, etc., then surround "exit" with \b. This is useful if you need to search for specific occurrences of a keyword or command. \b can also be used at just the beginning and end, if needed.

Download Youtube Playlist
This will download a Youtube playlist and mostly anything http://code.google.com/apis/youtube/2.0/reference.html#Video_Feeds The files will be saved by $id.flv

switch case of a text file

Save xkcd to a pdf with captions
Saves to a PDF with title and alt text of comic. As asked for on http://bbs.archlinux.org/viewtopic.php?id=91100 Change xkcd.com to dynamic.xkcd.com/comics/random for a random comic.


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