Commands by ktonga (1)

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continuously print string as if being entered from the keyboard
Cycles continuously through a string printing each character with a random delay less than 1 second. First parameter is min, 2nd is max. Example: 1 3 means sleep random .1 to .3. Experiment with different values. The 3rd parameter is the string. The sleep will help with battery life/power consumption. $ cycle 1 3 $(openssl rand 100 | xxd -p) Fans of "The Shining" might get a kick out of this: $ cycle 1 4 ' All work and no play makes Jack a dull boy.'

Find the modified time (mtime) for a file

generate random number

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

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

Using bash inline
There are two ways to use "here documents" with bash to fill stdin: The following example shows use with the "bc" command. a) Using a delimiter at the end of data: $ less-than less-than eeooff bc > k=1024 > m=k*k > g=k*m > g > eeooff 1073741824 b) using the "inline" verion with three less-than symbols: $ less-than less-than less-than "k=1024; m=k*k; g=k*m; g" bc 1073741824 One nice advantage of using the triple less-than version is that the command can easily be recalled from command line history and re-executed. PS: in this "description", I had to use the name "less-than" to represent the less-than symbol because the commandlinefu input text box seems to eat up the real less-than symbols. Odd.

grep lines containing two consecutive hyphens

Check to make sure the whois nameservers match the nameserver records from the nameservers themselves
Change the $domain variable to whichever domain you wish to query. Works with the majority of whois info; for some that won't, you may have to compromise: domain=google.com; for a in $(whois $domain | grep "Domain servers in listed order:" --after 3 | grep -v "Domain servers in listed order:"); do echo ">>> Nameservers for $domain from $a

Selecting a random file/folder of a folder
random file from files in directory

Live stream a remote desktop over ssh using only ffmpeg
Play with the framerate option '-r' to scale back bandwidth usage. The '-s' option is the captured screan area, not the rescaled size. If you want to rescale add a second '-s' option after '-i :0'. Rescaling smaller will also decrease bandwidth.


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