Commands by DNSpyder (1)

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Quickly graph a list of numbers
Useful when you've produced a large file of numbers, and want to quickly see the distribution. The value of y halfway along the x axis is the median. Simple! Just create the listOfNumbers.txt file with a number on each line to try it out.

Display ncurses based network monitor
Nload is part of nload package, tested under Debian. Nload display network bandwidth statistics, -u m options stands for MBit unit measure.

Change host name
With sed you can replace strings on the fly.

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" }

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

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

send kernel log (dmesg) notifications to root via cron
this is helpful because dmesg is where i/o errors, etc are logged to... you will also be able to see when the system reboots or someone attaches a thumb drive, etc. don't forget to set yourself up in /etc/aliases to get roots email.

check open ports without netstat or lsof

Extract JPEG images from a PDF document
This will extract all DCT format images from foo.pdf and save them in JPEG format (option -j) to bar-000.jpg, bar-001.jpg, bar-002.jpg, etc. Inspired by http://stefaanlippens.net/extract-images-from-pdf-documents

Sort the size usage of a directory tree by gigabytes, kilobytes, megabytes, then bytes.
Since coreutils 7.6 provides sort -h


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