Commands tagged recursive (36)

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Query ip pools based on successive netnames via whois
Useful if you f.i. want to block/allow all connections from a certain provider which uses successive netnames for his ip blocks. In this example I used the german Deutsche Telekom which has DTAG-DIAL followed by a number as netname for the dial in pools. There are - as always ;) - different ways to do this. If you have seq available you can use $ net=DTAG-DIAL ; for i in `seq 1 30`; do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; done or without seq you can use bash brace expansion $ net=DTAG-DIAL ; for i in {1..30}; do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; done or if you like while better than for use something like $ net=DTAG-DIAL ; i=1 ; while true ; do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; test $i = 30 && break ; i=$(expr $i + 1) ; done and so on.

Press a key automatically
Press a key automatically via xvkbd.

recursively walk down no more than three levels and grab any file with an extension of mp3, mpg, mpeg, or avi

Edit a script that's somewhere in your path.
Often I need to edit a bash or perl script I've written. I know it's in my path but I don't feel like typing the whole path (or I don't remember the path).

JSON processing with Python
Validates and pretty-prints the content fetched from the URL.

count match string lines from file(s)

Create QR codes from a URL.
QR codes are those funny square 2d bar codes that everyone seems to be pointing their smart phones at. Try the following... $ qrurl http://xkcd.com Then open qr.*.png in your favorite image viewer. Point your the bar code reader on your smart phone at the code, and you'll shortly be reading xkcd on your phone. URLs are not the only thing that can be encoded by QR codes... short texts (to around 2K) can be encoded this way, although this function doesn't do any URL encoding, so unless you want to do that by hand it won't be useful for that.

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

Join lines
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//g' file.txt

Pick a random line from a file


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