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E-mail a traditional Berkeley mbox to another recipient as individual e-mails.

Copy ssh keys to user@host to enable password-less ssh logins.
Alternative for machines without ssh-copy-id

Save your sessions in vim to resume later
Creates a full snapshot of your current vim session, including tabs, open buffers, cursor positions, everything. Can be resumed with vim -S . Useful for those times when you HAVE to close vim, but you don't want to lose all your hard-opened buffers and windows. The ! will cause vim to overwrite the file if it already exists. It is not necessary, but useful if you frequently save to the same file (like session.vim or something).

Clean swap area after using a memory hogging application
When you run a memory intensive application (VirtualBox, large java application, etc) swap area is used as soon as memory becomes insufficient. After you close the program, the data in swap is not put back on memory and that decreases the responsiveness. Swapoff disables the swap area and forces system to put swap data be placed in memory. Since running without a swap area might be detrimental, swapon should be used to activate swap again. Both swapoff and swapon require root privileges.

A function to find the newest file in a directory

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

resolve hostname to IP our vice versa with less output
inverted version: resolveip -s 216.34.181.xxx freshmeat.net

Are the two lines anagrams?
This works by reading in two lines of input, turning each into a list of one-character matches that are sorted and compared.

seconds since epoch to ISO timestamp
No need to use perl, awk, nor /usr/bin/date -- bash's "printf" builtin will do it.

Create a bunch of dummy files for testing
Sometimes I need to create a directory of files to operate on to test out some commandlinefu I am cooking up. The main thing is the range ({1..N}) expansion.


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