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Create strong, but easy to remember password
Why remember? Generate! Up to 48 chars, works on any unix-like system (NB: BSD use md5 instead of md5sum)

List the CPU model name
Extracts the model name of the CPU and displays it on screen.

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" }

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Change the From: address on the fly for email sent from the command-line
It's very common to have cron jobs that send emails as their output, but the From: address is whatever account the cron job is running under, which is often not the address you want replies to go to. Here's a way to change the From: address right on the command line. What's happening here is that the "--" separates the options to the mail client from options for the sendmail backend. So the -f and -F get passed through to sendmail and interpreted there. This works on even on a system where postfix is the active mailer - looks like postfix supports the same options. I think it's possible to customize the From: address using mutt as a command line mailer also, but most servers don't have mutt preinstalled.

finding cr-lf files aka dos files with ^M characters
Looking for carriage returns would also identify files with legacy mac line endings. To fix both types: $ perl -i -pe 's/\r\n?/\n/g' $(find . -type f -exec fgrep -l $'\r' "{}" \;)

Use nroff to view the man pages
Using nroff , it is possible to view the otherwise garbled man page with col command.

Console clock
Shows a simple clock in the console -t param removes the watch header Ctrl-c to exit

list block devices
Shows all block devices in a tree with descruptions of what they are.

Dumping Audio stream from flv (using ffmpeg)


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