Commands by mdelatorre (1)

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Redirect incoming traffic to SSH, from a port of your choosing
Stuck behind a restrictive firewall at work, but really jonesing to putty home to your linux box for some colossal cave? Goodness knows I was...but the firewall at work blocked all outbound connections except for ports 80 and 443. (Those were wide open for outbound connections.) So now I putty over port 443 and have my linux box redirect it to port 22 (the SSH port) before it routes it internally. So, my specific command would be: $iptables -t nat -A PREROUTING -p tcp --dport 443 -j REDIRECT --to-ports 22 Note that I use -A to append this command to the end of the chain. You could replace that with -I to insert it at the beginning (or at a specific rulenum). My linux box is running slackware, with a kernel from circa 2001. Hopefully the mechanics of iptables haven't changed since then. The command is untested under any other distros or less outdated kernels. Of course, the command should be easy enough to adapt to whatever service on your linux box you're trying to reach by changing the numbers (and possibly changing tcp to udp, or whatever). Between putty and psftp, however, I'm good to go for hours of time-killing.

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" }

convert single digit to double digits
works only in zsh, requires autoload zmv

Install pip with Proxy
Installs pip packages defining a proxy

Copy structure
Clone directory structure without the files

SSH tunneling self-connection
- port 8080 on localhost will be a SOCKSv5 proxy - at localhost:localport1 you will be connected to the external source server1:remoteport1 and at bind_address2:localport2 to server2:remoteport2 - you will be using only IPv4 and arcfour/blowfish-cbc, in order to speed up the tunnel - if you lose the connection, autossh will resume it at soon as possible - the tunnel is here a background process, wiithout any terminal window open

Notepad in a browser (type this in the URL bar)
It doesn't save your notes, but it's great for jotting something down quickly.

Convert multiple flac files to mp3
make sure that flac and lame are installed sudo apt-get install lame flac

Start a SOCKS proxy to avoid a restrictive firewall
You may go to Internet by means of your home ssh server. You must configure your local proxy to send traffic through the proxy. Many programs allows that: firefox, pidgin, skype, gnome, etc. Your home ssh server must listen in any of the ports permitted by your enterprise firewall. That usually includes 80 and 443.

Remove ( color / special / escape / ANSI ) codes, from text, with sed
Remove ( color / special / escape / ANSI ) codes, from text, with sed Credit to the original folks who I've copied this command from. The diff here is: Theirs: [m|K] Theirs is supposed to remove \E[NUMBERS;NUMBERS[m OR K] This statement is incorrect in 2 ways. 1. The letters m and K are two of more than 20+ possible letters that can end these sequences. 2. Inside []'s , OR is already assumed, so they are also looking for sequences ending with | which is not correct. This : [a-zA-Z] This resolves the "OR" issue noted above, and takes care of all sequences, as they all end with a lower or upper cased letter. This ensures 100% of any escape code 'mess' is removed.


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