Alias two dots to move to parent directory. Put it into your .bashrc or .profile file. Show Sample Output
Files containing ascii art (e.g. with .nfo extension) are typically not correctly reproduced at the command line when using cat. With iconv one can easily write a wrapper to solve this:
#!/bin/bash
if [ -z "$@" ]; then echo "Usage: $(basename $0) file [file] ..."
else iconv -f437 -tutf8 "$@"; fi
exit 0
I often need to know of my directory in the PATH, which one DOES NOT exist. This command answers that question * This command uses only bash's built-in commands * The parentheses spawn a new sub shell to prevent the modification of the IFS (input field separator) variable in the current shell
for example if you did a:
ls -la /bin/ls
then
ls !$
is equivalent to doing a
ls /bin/ls
I realize there's a few of these out there, but none exactly in this form, which seems the cleanest to me
Sometimes you have a script that needs and inputfile for execution. If you don't want to create one because it may contain only one line you can use the `
mysql -uuser -ppass dbname < <(echo "SELECT * FROM database;")
This can be very usefull when working with mysql as I showed in the example code above. This will create a temporary file that is used to execute mysql and for example select all entrys from a specific database.
Really bored during class so I made this... Basically, you hold period (or whatever) and hit enter after a second and you need to make the next line of periods the same length as the previous line... My record was 5 lines of the same length. It's best if you do it one handed with your pointer on period and ring on enter.
I like the other three versions but one uses nested loops and another prints every color on a separate line. Both versions fail to reset colors before giving the prompt back. This version uses the column command to print a table so all the colors fit on one screen. It also resets colors back to normal before as a last step.
You have a script where =ALL= STDERR should be redirected to STDIN and you don't want to add "2>&1" at the end of each command...
E.G.:
ls -al /foo/bar 2>&1
Than just add this piece of code at the beginning of your script!
I hope this can help someone. :)
This command will give you the same list of files as "find /etc/ -name '*killall' | xargs ls -l". In a simpler format just do 'ls /etc/**/file'. It uses shell globbing, so it will also work with other commands, like "cp /etc/**/sshd sshd_backup". Show Sample Output
List all commands present on system by folder.
PATH contains all command folder separated by ':'. With ${PATH//:/ }, we change ':' in space and create a list of folder for ls command.
Show Sample Output
[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. ☺)
Show Sample Output
Simple and easy to remember, if it already exists then it just ignores it.
Uses the extremely cool utilities netcat and expect. "expect" logs in & monitors for server PING checks. When a PING is received it sends the PONG needed to stay connected. IRC commands to try: HELP, TIME, MOTD, JOIN and PRIVMSG The "/" in front of IRC commands are not needed, e.g. type JOIN #mygroup Learn about expect: http://tldp.org/LDP/LGNET/issue48/fisher.html The sample output shows snippets from an actual IRC session. Please click UP button if you like it! Show Sample Output
This command create a new temp directory using mktemp (to avoid collisions) and change the current working directory to the created directory. Show Sample Output
When you use a "for" construct, it cycles on every word. If you want to cycle on a line-by-line basis (and, well, you can't use xargs -n1 :D), you can set the IFS variable to . Show Sample Output
To ensure that it will never come back, you can edit /etc/modprobe.d/blacklist Add "blacklist pcspkr" sans quotes
This command displays a simple menu of file names in the current directory. After the user made a choice, the command invokes the default editor to edit that file. * Without the break statement, the select command will loop forever * Setting the PS3 prompt is optional * If the user types an invalid choice (such as the letter q), then the variable $f will become an empty string. * For more information, look up the bash's select command Show Sample Output
Joker wants an email if the Brand X server is down. Set a cron job for every 5 mins with this line and he gets an email when/if a ping takes longer than 3 seconds. Show Sample Output
I often need to extract a function from a bash script and this command will do it. Show Sample Output
It's the rename-tool from debians perl-package.
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