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Remove all mail in Postfix mail queue.

Stripping ^M at end of each line for files
just deletes to rogue CR from dos files, and tr is always available.

output your microphone to a remote computer's speaker

Simple server which listens on a port and prints out received data
Sometimes you need a simple server which listens on a port and prints out received data. Example: Consider you want to know, which data is posted by a homepage to a remote script without analysing the html code! A simple way to do this is to save the page to your computer, substitude all action="address" with action="localhost:portnumber", run 'ncat -l portnumber' and open the edited page with your browser. If you then submit the form, ncat will print out the http-protocol with all the posted data.

find an unused unprivileged TCP port
Not really better - just different ;) There's probably a really simple solution out there somewhere...

Continue a current job in the background

list block level layout

Convert ascii string to hex
If you're going to use od, here's how to suppress the labels at the beginning. Also, it doesn't output the \x, hence the sed command at the end. Remove it for space separated hex values instead

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

Unpack .tgz File On Linux
With -a you don't care about file type (bz2, gzip, etc.)


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