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Find all files with colons and replace with underscores; current directory and below (recursive).

Get your outgoing IP address
Get your external ip adress thanks to http://www.icanhazip.com

Working random fact generator
Though without infinite time and knowledge of how the site will be designed in the future this may stop working, it still will serve as a simple straight forward starting point. This uses the observation that the only item marked as strong on the page is the single logical line that includes the italicized fact. If future revisions of the page show failure, or intermittent failure, one may simply alter the above to read. $ wget randomfunfacts.com -O - 2>/dev/null | tee lastfact | grep \ | sed "s;^.*\(.*\).*$;\1;" The file lastfact, can then be examined whenever the command fails.

Insert the last argument of the previous command
for example if you did a: $ ls -la /bin/ls then $ ls !$ is equivalent to doing a $ ls /bin/ls

use wget to check if a remote file exists
put your link [url] to check if exist the remote file

copy timestamps of files from one location to another - useful when file contents are already synced but timestamps are wrong.
Sometimes when copying files from one place to another, the timestamps get lost. Maybe you forgot to add a flag to preserve timestamps in your copy command. You're sure the files are exactly the same in both locations, but the timestamps of the files in the new home are wrong and you need them to match the source. Using this command, you will get a shell script (/tmp/retime.sh) than you can move to the new location and just execute - it will change the timestamps on all the files and directories to their previous values. Make sure you're in the right directory when you launch it, otherwise all the touch commands will create new zero-length files with those names. Since find's output includes "." it will also change the timestamp of the current directory. Ideally rsync would be the way to handle this - since it only sends changes by default, there would be relatively little network traffic resulting. But rsync has to read the entire file contents on both sides to be sure no bytes have changed, potentially causing a huge amount of local disk I/O on each side. This could be a problem if your files are large. My approach avoids all the comparison I/O. I've seen comments that rsync with the "--size-only" and "--times" options should do this also, but it didn't seem to do what I wanted in my test. With my approach you can review/edit the output commands before running them, so you can tell exactly what will happen. The "tee" command both displays the output on the screen for your review, AND saves it to the file /tmp/retime.sh. Credit: got this idea from Stone's answer at http://serverfault.com/questions/344731/rsync-copying-over-timestamps-only?rq=1, and combined it into one line.

Make redirects to localhost via /etc/hosts more interesting
Normally when a site is blocked through /etc/hosts, traffic is just being redirected to a non-existent server that isn't going to respond. This helps get your point across a little more clearly than a browser timeout. Of course you could use any number of codes: http://en.wikipedia.org/wiki/List_of_HTTP_status_codes Obviously, this command can be added to init-rc.d, and more sophisticated responses can be given. Seems noteworthy to mention that the information sent from the browser can be parsed using the bash READ builtin (such as 'while read -t 1 statement; do parsing'), and the connection stays open until the script exits. Take care that you must use EXEC:'bash -c foo.sh', as 'execvp' (socat's method for executing scripts) invokes 'sh', not 'bash'.

Reduce PDF Filesize

Router discovery

Remote screenshot
Admittedly, I'd never have thought of this without the earlier examples, but here's one that you can execute from your workstation to just display the image from another, without separately doing a file transfer, etc. By the way, I hear a loud beep coming from the other room, so I guess it's not too stealthy :-D


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