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Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.
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Useful when you forget to use sudo for a command. "!!" grabs the last run command.
I often forget to sudo before editing a file I don't have write permissions on. When you come to save that file and get the infamous "E212: Can't open file for writing", just issue that vim command in order to save the file without the need to save it to a temp file and then copy it back again.
Really useful for when you have a typo in a previous command. Also, arguments default to empty so if you accidentally run:
echo "no typozs"
you can correct it with
^z
mtr combines the functionality of the traceroute and ping programs in a single network diagnostic tool.
As mtr starts, it investigates the network connection between the host mtr runs on and HOSTNAME. by sending packets with purposly low TTLs. It continues to send packets with low TTL, noting the response time of the intervening routers. This allows mtr to print the response percentage and response times of the internet route to HOSTNAME. A sudden increase in packetloss or response time is often an indication of a bad (or simply over‐loaded) link.
Next time you are using your shell, try typing ctrl-x e (that is holding control key press x and then e). The shell will take what you've written on the command line thus far and paste it into the editor specified by $EDITOR. Then you can edit at leisure using all the powerful macros and commands of vi, emacs, nano, or whatever.
To generate the keys use the command ssh-keygen
Prepending one or more spaces to your command won't be saved in history.
Useful for pr0n or passwords on the commandline.
Tested on BASH.
For when you want to flush all content from a file without removing it (hat-tip to Marc Kilgus).
If you bork your terminal by sending binary data to STDOUT or similar, you can get your terminal back using this command rather than killing and restarting the session. Note that you often won't be able to see the characters as you type them.
now you can acces the website by going to http://localhost:2001/
This is an alternative to cron which allows a one-off task to be scheduled for a certain time.
Query Wikipedia by issuing a DNS query for a TXT record. The TXT record will also include a short URL to the complete corresponding Wikipedia entry.You can also write a little shell script like:
$ cat wikisole.sh
#!/bin/sh
dig +short txt ${1}.wp.dg.cx
and run it like
./wikisole.sh unix
were your first option ($1) will be used as search term.
Particularly useful if you're mounting different drives, using the following command will allow you to see all the filesystems currently mounted on your computer and their respective specs with the added benefit of nice formatting.
When typing out long arguments, such as:
cp file.txt /var/www/wp-content/uploads/2009/03/
You can put that argument on your command line by holding down the ALT key and pressing the period '.' or by pressing <ESC> then the period '.'. For example:
cd 'ALT+.'
would put '/var/www/wp-content/uploads/2009/03/ as my argument. Keeping pressing 'ALT+.' to cycle through arguments of your commands starting from most recent to oldest. This can save a ton of typing.
The PID will only be printed if you're holding a root equivalent ID.
This will output the sound from your microphone port to the ssh target computer's speaker port. The sound quality is very bad, so you will hear a lot of hissing.
Makes a partition in ram which is useful if you need a temporary working space as read/write access is fast.
Be aware that anything saved in this partition will be gone after your computer is turned off.
Install SSHFS from http://fuse.sourceforge.net/sshfs.html
Will allow you to mount a folder security over a network.
Very useful for rerunning a long command changing some arguments globally.
As opposed to ^foo^bar, which only replaces the first occurrence of foo, this one changes every occurrence.
Useful for checking if there are differences between local and remote files.