Commands by ilovespam (3)

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Print a list of all hardlinks in the working directory, recursively
libpurple likes to hardlink files repeatedly. To ignore libpurple, use sed: | sed '/\.\/\.purple/d'

Bash function that saves bash functions to file from shell session
The simpler, 1-arg version is save_function(){ { date +"# %F.%T $1; declare -f "$1";}| tee -a ~/.bash_functions; }`

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 The command is untested under any other distros or less outdated kernels.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.

List Listen Port by numbers
Show TCP Listen ports sorted by number (bugs: IPV6 addresses not supported)

Open Sublime-text in current directory

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Simplification of "sed 'your sed stuff here' file > file2 && mv file2 file"

Print a monthly calendar with today's date highlighted
The cal command is handy, but sometimes you want to quickly see today's date highlighted. That's why I came up with this quick command. Much like http://www.commandlinefu.com/commands/view/1342/show-this-months-calendar-with-todays-date-highlighted but cleaner and more succinct.

Get names of files in /dev, a USB device is attached to
This command lists the names of your USB devices connected and what file in /dev they are using. It's pretty useful if you don't have an automount option in your desktop or you don't have any graphical enviroment.

Check if a process is running
Send signal 0 to the process. The return status ($?) can be used to determine if the process is running. 0 if it is, non-zero otherwise.


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