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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

Re-emerge all ebuilds with missing files (Gentoo Linux)

Mount a partition from dd disk image
Assuming we have a disk image, ie. created by $dd if=/dev/sda of=image.dd we can check the image's partition layout with $fdisk -ul image.dd then, we substitute "x" with starting sector of the partition we want to mount. This example assumes that the disk uses 512 B sectors

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

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

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"

Batch convert PNG to JPEG
Convert all PNG images in directory to JPEG using ImageMagick, and delete the old PNG images.

Generat a Random MAC address
Just increase the 1 at the end if you want to generate more than one. (Alternative to "| head -n N" you could use the -b flag of od: -b $[6*N]

Generate an XKCD #936 style 4 word password
The improvement of this command over Strawp's original alternative is that you can specify the size of the words, in this particular case words between 3 and 5 character's long. It also excludes words that contain apostrophes, if you'd rather keep those words simply substitue [^'] for .

Complete TCP Handshake on a given host-port
Try to perform a fully TCP 3 way handshake on for a given host-port with a timeout of 1s.


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