Commands tagged var (4)

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Output files without comments or empty lines
Filter comments and empty lines in files. I find this very useful when trying to find what values are actually set in a very long example config file. I often set an alias for it, like : alias nocomment='grep -v "^\($\|#\)"'

Print number of mb of free ram
Here we instead show a more real figure for how much free RAM you have when taking into consideration buffers that can be freed if needed. Unix machines leave data in memory but marked it free to overwrite, so using the first line from the "free" command will mostly give you back a reading showing you are almost out of memory, but in fact you are not, as the system can free up memory as soon as it is needed. I just noticed the free command is not on my OpenBSD box.

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

Show IP Address in prompt --> PS1 var
when working with many machines in a computer lab need to know the IP addr is very large, this is a simplistic solution to make things easier

Get the Volume labels all bitlocker volumes had before being encrypted
Get information of volume labels of bitlocker volumes, even if they are encrypted and locked (no access to filesystem, no password provided). Note that the volume labels can have spaces, but only if you name then before encryption. Renaming a bitlocker partition after being encrypted does not have the same effect as doing it before.

List all symbolic links in current directory
Tested with GNU and BSD ls.

find and replace tabs for spaces within files recursively

Split a tarball into multiple parts
Create a tar file in multiple parts if it's to large for a single disk, your filesystem, etc. Rejoin later with `cat .tar.*|tar xf -`

Puts every word from a file into a new line
Basically it creates a typical word list file from any normal text.

Display the standard deviation of a column of numbers with awk


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