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Get a stream feed from a Twitter user
*** CAREFULLY READ THE NOTES **** *** THIS DOES NOT WORK "OUT OF THE BOX" *** You'll need a few minutes of CAREFUL reading before making your own Twitter feed: In 2010 simple command line Twitter feed requests all stopped working because Twitter upgraded to SSL security. Https requests for a filtered Twitter stream feed now require a special header called "oauth_header". The benefit is that your stream feed and login info is securely encrypted. The bad news is that an "oauth_header" takes some work to build. Fortunately, four functions, imaginatively named step1, step2, step3 and step4 can be used to build a customized oauth_header for you in a few minutes. Now, go look at "step1" to start creating your own oauth_header!

Advanced python tracing
Trace python statement execution and syscalls invoked during that simultaneously

dump a single table of a database to file

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"

delete duplicate lines from a file and keep the order of the other lines
i wanted to delete all duplicate lines from .bash_history and keep the order of the other lines. the command cat's the file and adds line numbers, then sorts by the second column. afterwards uniq omits repeated lines, but skips the first field (the line number). then it sorts by the line numbers and at the end cuts the numbers off.

Open Remote Desktop (RDP) from command line having a custom screen size
This example uses xfreerdp, which builds upon the development of rdesktop. This example usage will also send you the remote machine's sound.

Download all mp3's listed in an html page

Does a traceroute. Lookup and display the network or AS names and AS numbers.
From the man page. lft ? display the route packets take to a network host/socket using one of several layer-4 protocols and methods; optionally show heuristic network information in transitu -A Enable lookup and display of of AS (autonomous system) numbers (e.g., [1]). This option queries one of several whois servers (see options 'C' and 'r') in order to ascertain the origin ASN of the IP address in question. By default, LFT uses the pWhoIs service whose ASN data tends to be more accurate and more timely than using the RADB as it is derived from the Internet's global routing table. -N Enable lookup and display of network or AS names (e.g., [GNTY-NETBLK-4]). This option queries Prefix WhoIs, RIPE NCC, or the RADB (as requested). In the case of Prefix WhoIs or RADB, the network name is displayed. In the case of RIPE NCC, the AS name is displayed.

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" }

Securely destroy data on given device hugely faster than /dev/urandom
This command generates a pseudo-random data stream using aes-256-ctr with a seed set by /dev/urandom. Redirect to a block device for secure data scrambling.


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