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Get a list of all browsable Samba shares on the target server.

Turn On/Off Keyboard LEDs via commandline
Usefull as a light blink to remember events, mails, intrusions, etc... yet another output Since nobody ever uses the scroll lock function... Usefull to interface a linux system with some hardware, for example, opto interfacing the keyboard led to a relay to remotely reset, etc. ( a simple LDR glued over the LED will do the trick ) xset led 3 turns on the third led, ie, Scroll lock xset -led 3 turns it off xset led 1 turns on Numerical Lock led ( doesn t work on all computer ) xset led 2 turns on Caps Lock led ( idem ) Using it as a reset watchdog, the relay expected light pulses. Shall the computer hangs, the relay releases and reset the machine ( discharge of a capacitor ) ;-)

Reinstall a Synology NAS without loosing any data from commandline.
Seen many questions how-to reinstall synology nas dsm without loosing data, here you go. Wait for a few min and then head over to http://nasip and setup your fresh installed nas.

Limit the cpu usage of a process
Similar to `cpulimit`, although `prlimit` can be found shipped with recent util-linux. Example: limit CPU consumption to 10% for a math problem which ordinarily takes up 100% CPU: Before: $ bc -l

shell function to underline a given string.
underline() will print $1, followed by a series of '=' characters the width of $1. An optional second argument can be used to replace '=' with a given character. This function is useful for breaking lots of data emitted in a for loop into sections which are easier to parse visually. Let's say that 'xxxx' is a very common pattern occurring in a group of CSV files. You could run $ grep xxxx *.csv This would print the name of each csv file before each matching line, but the output would be hard to parse visually. $ for i in *.csv; do printf "\n"; underline $i; grep "xxxx" $i; done Will break the output into sections separated by the name of the file, underlined.

Find which service was used by which port number

Use default value if unassigned
Will use variable value (for variable $my_dir, in this case), an assign a default value if there is none.

run last command with root
you will be sad after you run a command and find out it needs root, so you should run it again but with prefix sudo. so this line is to make it simple. just 'sudo !!'

list folders containing less than 2 MB of data
Just shortened the awk a bit and removed sed. Edit: I'm assuming there are no spaces in the path. To support white space in pathname try: $ awk '($1 < 2048) {sub(/^[0-9]+[ \t]+/,""); print $0}'

Submit command & rewrite orginal command
Similar to entering a command, but will not erase the command from the command line. Basically a shortcut from entering command, then pushing the up arrow key.


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