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Create new user with home dir and given password
The crypt function takes a password, key, as a string, and a salt character array which is described below, and returns a printable ASCII string which starts with another salt. It is believed that, given the output of the function, the best way to find a key that will produce that output is to guess values of key until the original value of key is found. from http://en.wikipedia.org/wiki/Crypt_(Unix)

validate json
I have this saved as jsonlint chmodded +x and file.js is instead $1, but YMMV

escape any command aliases
e.g. if rm is aliased for 'rm -i', you can escape the alias by prepending a backslash: rm [file] # WILL prompt for confirmation per the alias \rm [file] # will NOT prompt for confirmation per the default behavior of the command

Colorized grep in less
Get your colorized grep output in less(1). This involves two things: forcing grep to output colors even though it's not going to a terminal and telling less to handle those properly.

Show the UUID of a filesystem or partition
Shows the UUID of a filesystem or partition that can be used in kernel root options and in fstab. Run it without the -u option to generate more information. eg: ~/ sudo vol_id /dev/sda2 ID_FS_USAGE=other ID_FS_TYPE=swap ID_FS_VERSION=2 ID_FS_UUID=27fca13d-97b7-4d28-882c-6d03353f0a82 ID_FS_UUID_ENC=27fca13d-97b7-4d28-882c-6d03353f0a82 ID_FS_LABEL= ID_FS_LABEL_ENC=

display a smiling smiley if the command succeeded and a sad smiley if the command failed
you could save the code between if and fi to a shell script named smiley.sh with the first argument as and then do a smiley.sh to see if the command succeeded. a bit needless but who cares ;)

Reset hosed terminal,
stty sane resets the tty to basic usable function. The ^J is a newline -- sometimes CR/LF interpretation is broken so use the ^J explicitly.

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

Create directory named after current date
Not a discovery but a useful one nontheless. In the above example date format is 'yyyymmdd'. For other possible formats see 'man date'. This command can be also very convenient when aliased to some meaningful name: $ alias mkdd='mkdir $(date +%Y%m%d)'

list files recursively by size


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