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Generat a Random MAC address

backup and remove files with access time older than 5 days.
create an archive of files with access time older than 5 days, and remove original files.

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" }

Stream audio over ssh
This will allow you to convert an audio file to wav format, and send it via ssh to a player on the other computer, which will open and play it there. Of course, substitute your information for the sound file and remote address You do not have to use paplay on the remote end, as it is a PulseAudio thing. If the remote end uses ALSA, you should use aplay instead. If it uses OSS, you should berate them about having a lousy sound system. Also, you're not limited to transmitting encoded as wav either, it's just that AFAIK, most systems don't come with mp3 codecs, but will play wav files fine. If you know SoX is installed on the remote end and has mp3 codecs, you can use the following instead: $ cat Klaxon.mp3 |ssh thelab@company.com play -t mp3 - this will transmit as mp3. Again, use your specific information. if you're not playing mp3s, use another type with the -t option

Check your hard drive for bad blocks (destructive)
WARNING!!! ALL DATA WILL BE LOST!!! This command should ONLY be run on drives that are meant to be wiped. Data destruction will result from running this command with the '-w' switch. You may run this command with the '-n' switch in place of '-w' if you want to retain all data on the drive, however, the test won't be as detailed, since the '-n' switch provides a non-destructive read-write mode only, whereas '-w' switch actually writes patterns while scanning for bad blocks.

list block devices
Shows all block devices in a tree with descruptions of what they are.

Last month
Work out last months value

Check wireless link quality with dialog box
The variable WIRELESSINTERFACE indicates your wireless interface

Get decimal ascii code from character
printf treats first char after single ' as numeric equivalent

Monitor open connections for httpd including listen, count and sort it per IP
It's not my code, but I found it useful to know how many open connections per request I have on a machine to debug connections without opening another http connection for it. You can also decide to sort things out differently then the way it appears in here.


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