Linux

/etc = system & application settings/etc/skel = “skeleton” files used to create user accounts /lib = security files, system modules, & libraries containing software libraries & information databases /opt = pre-loaded software packages /usr/lib =...

After typing ls -l, you’ll get a list of all files & directories, along with other information, including permissions associated with those files & directories. These permissions might look like this: -rw-rw-r-- lrwxrwxrwx -rwxr-xr-x These...

The apropos command searches a database of commands, using keywords: apropos Note that your keyword might not work. So try different keywords until it does! If apropos does not work, you probably need to rebuild the whatis database with this...

This is called command stacking.

To stack commands, use a semicolon (;) between commands, like this:

cd /etc ; ls -l

Be very careful when command stacking, especially when deleting or moving files! Make sure what you typed is what you want!

To see and choose previous commands, use the up arrow. Up to 500 of your last commands are stored in .bash_history (note the period before the file name). To automatically run the previous command, use this: !! To run a command that you ran a while...

locate = find data files, programs, directories, & objects matching your search. For example: locate license Since you usually receive quite a long list when running locate, you’ll probably want to do this: locate | more -or- locate | less...

Add the following lines to /etc/rc.d/rc.local:

echo -n "Turning on numlock ... "
for tty in /dev/tty[1-6] /dev/tty1[2]; do
setleds -D +num < $tty & done echo "done "