Commands tagged calculation (10)

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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"

output length of longest line

Simulate slow network connection locally
Replace 500ms by the desired delay. To remove it: sudo tc qdisc del dev lo root netem delay 500ms

Reverse ssh
Both hosts must be running ssh and also the outside host must have a port forwarded to port 22.

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"

Easily find latex package documentation
If the pdf/dvi/etc documentation for a latex package is already part of your local texmf tree, then texdoc will find and display it for you. If the documentation is not available on your system, it will bring up the package's webpage at CTAN to help you investigate.

Simple Video Surveillance by email
This takes a picture (with the web cam) every 5 minutes, and send the picture to your e-mail. Some systems support mail -a "References: " so that all video surveillance emails are grouped in a single email thread. To keep your inbox clean, it is still possible to filter and move to trash video surveillance emails (and restore these emails only if you really get robbed!) For instance with Gmail, emails sent to [email protected] can be filtered with "Matches: DeliveredTo:[email protected]"

Get the Volume labels all bitlocker volumes had before being encrypted
Get information of volume labels of bitlocker volumes, even if they are encrypted and locked (no access to filesystem, no password provided). Note that the volume labels can have spaces, but only if you name then before encryption. Renaming a bitlocker partition after being encrypted does not have the same effect as doing it before.

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.

show the real times iso of epochs for a given column
When you have one of those (log)files that only has epoch for time (since no one will ever look at them as a date) this is a way to get the human readable date/time and do further inspection. Mostly perl-fu :-/


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