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list files in mtime order
Simple but useful; list files in the current directory in mtime order. Useful if you've been working on something and then take a day or two off.

Down for everyone or just me?
Check if a site is down with downforeveryoneorjustme.com

Rip a CD/DVD to ISO format.
An easy method to generate ISOs from CD/DVD media.

Output a SSL certificate start or end date
A quick and simple way of outputting the start and end date of a certificate, you can simply use 'openssl x509 -in xxxxxx.crt -noout -enddate' to output the end date (ex. notAfter=Feb 01 11:30:32 2009 GMT) and with the date command you format the output to an ISO format. For the start date use the switch -startdate and for end date use -enddate.

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

Use mplayer to save video streams to a file
I use this command to save RTSP video streams over night from one of our national TV stations, so I won't have to squeeze the data through my slow internet connection when I want to watch it the next day. For ease of use, you might want to put this in a file: #!/bin/bash FILE="`basename \"$1\"`" mplayer -dumpstream -dumpfile "$FILE" -playlist "$1"

mtr, better than traceroute and ping combined
mtr combines the functionality of the traceroute and ping programs in a single network diagnostic tool. As mtr starts, it investigates the network connection between the host mtr runs on and HOSTNAME. by sending packets with purposly low TTLs. It continues to send packets with low TTL, noting the response time of the intervening routers. This allows mtr to print the response percentage and response times of the internet route to HOSTNAME. A sudden increase in packetloss or response time is often an indication of a bad (or simply over‐loaded) link.

Diff two directories by finding and comparing the md5 checksums of their contents.
Compute the md5 checksums for the contents of two mirrored directories, then sort and diff the results. If everything matches, nothing is returned. Otherwise, any checksums which do not match, or which exist in one tree but not the other, are returned. As you might imagine, the output is useful only if no errors are found, because only the checksums, not filenames, are returned. I hope to address this, or that someone else will!

Getting the last argument from the previous command

list files recursively by size


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