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Nicely display mem usage with ps
Nicely display mem usage with ps.

Downlaoad websites to 5 level and browse offline!
Download Websites to 5 Level and browse offline! -k -> convert-links (to browse offline) -r -> recursive download -l 5 -> level 5 example. http://gentoo-install.com :-)

Backup of a partition
Clone a partion with tar.

Using awk to sum/count a column of numbers.
Takes a input file (count.txt) that looks like: 1 2 3 4 5 It will add/sum the first column of numbers.

Start screen with name and run command
Runs an instance of screen with name of "name_me" and command of "echo "hi"" To reconnect to screen instance later use: screen -r name_me

strip non-constant number of directories from tar archive while decompressing
If you want to decompress the files from an archive to current directory by stripping all directory paths, use --transform option to strip path information. Unfortunately, --strip-components option is good if the target files have same and constant depth of folders. The idea was taken from http://www.unix.com/solaris/145941-how-extract-files-tar-file-without-creating-directories.html

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

Perform a branching conditional
This will perform one of two blocks of code, depending on the condition of the first. Essentially is a bash terniary operator. To tell if a machine is up: $ ping -c1 machine { echo succes;} || { echo failed; } Because of the bash { } block operators, you can have multiple commands $ ping -c1 machine && { echo success;log-timestamp.sh }|| { echo failed; email-admin.sh; } Tips: Remember, the { } operators are treated by bash as a reserved word: as such, they need a space on either side. If you have a command that can fail at the end of the true block, consider ending said block with 'false' to prevent accidental execution

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Delete all empty lines from a file with vim
If you need to delete lines that may contain space characters (such as tabs or spaces) as well as empty ones, try: $:v/\S/d Just an alternative.


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