Commands by dragonauta (3)

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Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Erase DVD RW

Convert wma to mp3@128k
Convert all wma to mp3@128k with ffmpeg into directory.

Alert on high ping to know if it's really laggy while playing
Online games have pretty good lag compensation nowadays, Sometimes though, you really want to get some warning about your latency, e.g. while playing Diablo III in Hardcore mode, so you know when to carefully quit the game b/c your flatmate started downloading all his torrents at once. This is done on Darwin. On Linux/*nix you would need to find another suitable command instead of `say` to spell out your latency. And I used fping because it's a little bit easier to get the latency value needed. Something similar with our regular ping command could look like this: $ while :; do a=$(ping -c1 google.com | grep -o 'time.*' | cut -d\= -f2 | cut -d\ -f1 | cut -b1-4); [[ $a > 40 ]] && say "ping is $a"; sleep 3; done

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

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"

SAR - List the average memory usage for all days recorded under '/var/log/sa/*' using sar -r.

Find files that have been modified on your system in the past 60 minutes
Useful mainly for debugging or troubleshooting an application or system, such as X11, Apache, Bind, DHCP and others. Another useful switch that can be combined with -mmin, -mtime and so forth is -daystart. For example, to find files that were modified in the /etc directory only yesterday: $ sudo find /etc -daystart -mtime 1 -type f

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"

run a command whenever a file is touched
This is useful if you'd like to see the output of a script while you edit it. Each time you save the file the command is executed. I thought for sure something like this already exists - and it probably does. I'm on an older system and tend to be missing some useful things. Examples: $ ontouchdo yourscript 'clear; yourscript somefiletoparse' Edit yourscript in a separate window and see new results each time you save. $ ontouchdo crufty.html 'clear; xmllint --noout crufty.html 2>&1 | head' Keep editing krufty.html until the xmllint window is empty. Note: Mac/bsd users should use stat -f%m. If you don't have stat, you can use perl -e '$f=shift; @s=stat($f); print "$s[9]\n";' $1


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