'visudo' is installed by default on most Unix-like systems. If not installed, you can get it from the 'sudo' package. 'visudo' will use the text editor found in your $EDITOR variable, whether it's vi, vim, emacs, nano or gedit. After making changes to the /etc/sudoers file, visudo will check for syntax errors, and notify you of them. This is better than 'vi /etc/sudoers', because of this capability. Rule #1 of system administration- if there is a tool that exists for editing config files, use the tool.

Merge all pdf files in the directory into one pdf file (the out.pdf file)

Can pipe to tail or change the awk for for file size, groups, users, etc.

Lockstat will sample the kernel 977 times per second, and print out the functions that it sees executing on the CPU during the sample. The -s 10 switch tells lockstsat to not only print that function, but also show the call stack (up to 10 deep).

create tar.bz2 package from files "-type f" modificated today "-mtime -1" in ~/project

rsync from source to dest all between >30

command to turn off your computer when you go home and can not wait

over works like 'more' or 'less', but it pretty print the source code

If you spend most of your time in front of the terminal, leave is a useful reminder. Leave can have absolute form: leave 1555 reminds you to leave at 3:55PM

This command is almost the same as 'ls -a', but it does not display the current dir (.) or parent (..)

-t, --target-directory=DIRECTORY (copy all SOURCE arguments into DIRECTORY).

Display commands and their arguments as they are executed. Useful for debugging shell scripts.

If your customer deletes a file that is still in use by a process, that space does not get freed up (will not show up in df) until that process either closes the file on its own, or is killed.

* size must be 640?480 pixels

* only has 14 colors

* save it in XPM format

Edit /boot/grub/menu.lst and add

splashimage=(hd0,0)/boot/grub/grubimg.xpm

make sure for your path name and hard disk

NOT MINE! Taken from hackzine.com blog.

It creates a tree-style output of all the (sub)folders and (sub)files from the current folder and down(deeper)

Quoting some of hackzine's words

"Murphy Mac sent us a link to a handy find/sed command that simulates the DOS tree command that you might be missing on your Mac or Linux box. [..split...] Like most things I've seen sed do, it does quite a bit in a single line of code and is completely impossible to read. Sure it's just a couple of substitutions, but like a jack in the box, it remains a surprise every time I run it."

This command will kill all processes using a directory. It's quick and dirty. One may also use a -9 with kill in case regular kill doesn't work. This is useful if one needs to umount a directory.

For use in scripts this command is very usefull

create tree of dir's in one command

change ":" in path for new line and associate word path to var $PATH

"." is current dir, maxdepth is the level, -print0 | xargs -0 fix spaces in names, -i interactive , ./ is the current dir {} actual name , and {,.bak} is the atual name + bak

Running 'cpan Module::Name' will install that module from CPAN. This is a simple way of using a similar command to install a packaged Perl module from a Debian archive using apt-get.

Ever needed to look at the Perl source of an installed module on your system? This works in 90% of cases.

This adds all new files to SVN recursively. It doesn't work for files that have spaces in their name, but why would you create a file with a space in its name in the first place?