Commands using echo (1,545)

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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

Run the last command as root
Same as `sudo !!`. If you do not have permission to be sudo or sudo does not installed on your system, you can use this.

Change pidgin status
Thanks for the comment oshazard, i wasn't aware of purple-remote existence.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

add repeated watermark to image

echo something backwards
NAME rev - reverse lines of a file or files SYNOPSIS rev [file ...] DESCRIPTION The rev utility copies the specified files to the standard output, reversing the order of characters in every line. If no files are specified, the standard input is read. AVAILABILITY The rev command is part of the util-linux-ng package and is available from ftp://ftp.kernel.org/pub/linux/utils/util-linux-ng/.

Find usb device
I often use it to find recently added ou removed device, or using find in /dev, or anything similar. Just run the command, plug the device, and wait to see him and only him

sort ugly text
Often, when sorting you want the sort to ignore extraneous characters. The b, d, and f tell sort to ignore leading blanks, use 'dictionary order' (ignore punctuation), and ignore (fold) case. Add a "u" if you only want one copy of duplicate lines. This is a great command to use within vim to sort lines of text, using !}sort -bdf

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Tell what is encoded in a float, given its HEX bytes
It handles all possible combination of the hex bytes, including NaNs, Infinities, Normalized and Subnormal Numbers... $ This crazy DC stuff spent me a few days to write, optimize, polish and squeeze so that it works within the tight 255 character bound... $ You can modify it easily for other IEEE754 numbers, say, half, double, double-extended, quadruple $ (I hope someone will find this useful and submit more dc code to commandlinefu!)


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