Commands using cat (514)

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New command with the last argument of the previous command.

Use top to monitor only all processes with the same name fragment 'foo'
Like command 10870, but no need for sed

Runs previous command but replacing
Replaces the first instance of 'foo' with 'bar'. To replace all instances of 'foo' with 'bar': !!:gs/foo/bar/

oneliner to transfer a directory using ssh and tar
this will tar/send/untrar a whole directory.

sum a column of numbers

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

Add Password Protection to a file your editing in vim.
While I love gpg and truecrypt there's some times when you just want to edit a file and not worry about keys or having to deal needing extra software on hand. Thus, you can use vim's encrypted file format. For more info on vim's encrypted files visit: http://www.vim.org/htmldoc/editing.html#encryption

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Selecting a random file/folder of a folder
Also looks in subfolders

Put public IP address in a variable


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