Commands using ssh (347)

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Broadcast your shell thru port 5000
Doesn't work so well if you connect from windows. Linux only sends LF where windows wants CRLF. The alternative command works better with windows, however it uses script and a named pipe.

get diskusage of files modified during the last n days
get diskusage of files (in this case logfiles in /var/log) modified during the last n days: $ sudo find /var/log/ -mtime -n -type f | xargs du -ch n -> last modified n*24 hours ago Numeric arguments can be specified as +n for greater than n, -n for less than n, n for exactly n. => so 7*24 hours (about 7 days) is -7 $ sudo find /var/log/ -mtime -7 -type f | xargs du -ch | tail -n1

convert a web page into a png
This requires the command-line print extension (see #2861 for more details). I use it to make up complex images with formatted text using CSS and whatnot. It's a lot slicker than imagemagick for certain things. Now imagine using a local webserver with PHP and a database to generate the images. Oh, the possibilities...

Benchmark SQL Query
Benchmark a SQL query against MySQL Server. The example runs the query 10 times, and you get the average runtime in the output. To ensure that the query does not get cached, use `RESET QUERY CACHE;` on top in the query file.

Process command output line by line in a while loop
This snippet allows to process the output of any bash command line by line.

list processes with established tcp connections (without netstat)
Uses lsof to list open network connections (file descriptors), grepping for only those in an established state

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Rename files in batch

Binary clock
displays current time in "binary clock" format (loosely) inspired by: http://www.thinkgeek.com/homeoffice/lights/59e0/ "Decoding": 8421 .... - 1st hour digit: 0 *..* - 2nd hour digit: 9 (8+1) .*.. - 1st minutes digit: 4 *..* - 2nd minutes digit: 9 (8+1) Prompt-command version: PROMPT_COMMAND='echo "10 i 2 o $(date +"%H%M"|cut -b 1,2,3,4 --output-delimiter=" ") f"|dc|tac|xargs printf "%04d\n"|tr "01" ".*"'

urldecoding with one pure BASH builtin
You can use ordinary printf to convert "%23%21%2fbin%2fbash" into "#!/bin/bash" with no external utilities, by using a little known printf feature -- the "%b" specifier converts shell escapes. Replace % with \x and printf will understand the urlencoded string. BASH's printf has an extension to set a variable directly, too. So you get to convert urlencoded strings from garble to plaintext in one step with no externals and no backticks.


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