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Mount a temporary ram partition
For FreeBSD

Make vim open in tabs by default (save to .profile)
I always add this to my .profile rc so I can do things like: "vim *.c" and the files are opened in tabs.

Listen to BBC Radio from the command line.
This command lets you select from 10 different BBC stations. When one is chosen, it streams it with mplayer. Requires: mplayer with wma support.

Cleanup firefox's database.
Sqlite database keeps collecting cruft as time passes, which can be cleaned by the 'vacuum;' command. This command cleans up the cruft in all sqlite files relating to the user you have logged in as. This command has to be run when firefox is not running, or it will exit displaying the pid of the firefox running.

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

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"

prevent large files from being cached in memory (backups!)
We all know... $ nice -n19 for low CPU priority.   $ ionice -c3 for low I/O priority.   nocache can be useful in related scenarios, when we operate on very large files just a single time, e.g. a backup job. It advises the kernel that no caching is required for the involved files, so our current file cache is not erased, potentially decreasing performance on other, more typical file I/O, e.g. on a desktop.   http://askubuntu.com/questions/122857 https://github.com/Feh/nocache http://packages.debian.org/search?keywords=nocache http://packages.ubuntu.com/search?keywords=nocache   To undo caching of a single file in hindsight, you can do $ cachedel   To check the cache status of a file, do $ cachestats

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

convert unixtime to human-readable with awk
- convert unixtime to human-readable with awk - useful to read logfiles with unix-timestamps, f.e. squid-log: sudo tail -f /var/log/squid3/access.log | awk '{ print strftime("%c ", $1) $0; }

Mirror a directory structure from websites with an Apache-generated file indexes
wget/curl/friends are not good with mirroring files off websites, especially those with Apache-generated directory listings. These tools endlessly waste time downloading useless index HTML pages. lftp's mirror command does a better job without the mess.


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