Commands by nv21 (1)

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Exclude inserting a table from a sql import
Starting with a large MySQL dump file (*.sql) remove any lines that have inserts for the specified table. Sometimes one or two tables are very large and uneeded, eg. log tables. To exclude multiple tables you can get fancy with sed, or just run the command again on subsequently generated files.

Install Linux Kernel Headers on Debian-based systems
Install the Linux kernel headers for currently running kernel version on Debian-based systems via apt-get

Generate a random password 30 characters long
This command is similar to the alternate, except with head(1), you can pick as many passwords as you wish to generate by changing the number of lines you wish to preview.

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"

Check if a string is into a variable
Returns true (0) if the string is into $var, or false (1) if not.

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.'

Recursive replace of directory and file names in the current directory.
This should work anywhere perl and grep is available. :P

run a VirtualBox virtual machine without a gui
you can launch a VirtualBox VM from the command line using VBoxManage, but that invokes it in a gui environment. If you want to just fire off your VM in the background, use VBoxHeadless as shown. To get the names and UUIDs of your VirtualBox VMs, type: $ VBoxManage list

Have an ssh session open forever
Open a ssh session opened forever, great on laptops losing Internet connectivity when switching WIFI spots.

Find last reboot time
Specific to OSX.


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