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Find usb device
I often use it to find recently added ou removed device, or using find in /dev, or anything similar. Just run the command, plug the device, and wait to see him and only him

Add an iptables rule on RH/CentOs before the reject
Rather then editing the /etc/sysconfig/iptables file, or during a kickstart doing some awk/sed magic, easily add a rule in the correct place within iptables

Create cheap and easy index.html file
If your admin has disabled Apache's directory index feature but you want to have a cheap way to enable it for one folder, this command will just create an index.html file with a link to each file in the directory (including the index.html file, which is not ideal but makes the command much simpler). The HTML isn't even remotely compliant, but it could easily be improved on. Also, the command needs to be run each time a file is added or removed to update the index.html file.

Immediately put execute permission on any file saved/created in $HOME/bin

Sort a character string
Sorts a character string, using common shell commands.

Clean up poorly named TV shows.
Replace 'SHOWNAME' with the name of the TV show. Add -n to test the command without renaming files. Check the 'sample output'.

Find default gateway

github push-ing behind draconian proxies!
If you are behind a restrictive proxy/firewall that blocks port 22 connections but allows SSL on 443 (like most do) then you can still push changes to your github repository. Your .ssh/config file should contain: Host * ForwardX11 no TCPKeepAlive yes ProtocolKeepAlives 30 ProxyCommand /usr/local/bin/proxytunnel -v -p -d %h:443 Host User git Hostname ssh.github.com ChallengeResponseAuthentication yes IdentityFile ~/.ssh/id_rsa IdentitiesOnly yes Basically proxytunnel "tunnels" your ssh connection through port 443. You could also use corkscrew or some other tunneling program that is available in your distro's repository. PS: I generally use "github.com" as the SSH-HOST so that urls of the kind [email protected]:USER/REPO.git work transparently :) You

find previously entered commands (requires configuring .inputrc)
[Click the "show sample output" link to see how to use this keystroke.]   Meta-p is one of my all time most used and most loved features of working at the command line. It's also one that surprisingly few people know about. To use it with bash (actually in any readline application), you'll need to add a couple lines to your .inputrc then have bash reread the .inputrc using the bind command:   $ echo '"\en": history-search-forward' >> ~/.inputrc   $ echo '"\ep": history-search-backward' >> ~/.inputrc   $ bind -f ~/.inputrc     I first learned about this feature in tcsh. When I switched over to bash about fifteen years ago, I had assumed I'd prefer ^R to search in reverse. Intuitively ^R seemed better since you could search for an argument instead of a command. I think that, like using a microkernel for the Hurd, it sounded so obviously right fifteen years ago, but that was only because the older way had benefits we hadn't known about.     I think many of you who use the command line as much as I do know that we can just be thinking about what results we want and our fingers will start typing the commands needed. I assume it's some sort of parallel processing going on with the linguistic part of the brain. Unfortunately, that parallelism doesn't seem to work (at least for me) with searching the history. I realize I can save myself typing using the history shortly after my fingers have already started "speaking". But, when I hit ^R in Bash, everything I've already typed gets ignored and I have to stop and think again about what I was doing. It's a small bump in the road but it can be annoying, especially for long-time command line users. Usually M-p is exactly what I need to save myself time and trouble.     If you use the command line a lot, please give Meta-p a try. You may be surprised how it frees your brain to process more smoothly in parallel. (Or maybe it won't. Post here and let me know either way. ☺)

Given $PID, print all child processes on stdout
Simpler.


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