Linux introduction

Why Linux? Powerful (remote) shell

Starting with Linux Start a terminal window

Terminal

Who

Where

What

Details

The Linux Manual pages ls –l What does the “ -l ” option do? man ls NAME ls - list directory contents... -l use a long listing format …

Directory structure

/homehome directories for the users /etcsystem configuration files /varsystem log files /binprograms /usr/binprograms /sbinadministrator programs /usr/sbinadministrator programs /tmptemporary work space /mntnetwork disks /mediaCD-rom/DVD/USB sticks

The root directory

A closer look at a file

File/Directory permissions ls -l drwxr-xr-x 2 penguin users … scripts drwxr-xr-x -Directory (yes/no) -right for user, group and others -read, write and execute/open directory Access flags owner groupfile/directory name user group other

Running the Perl script

Where is the perl program?

Processes

Stopping a process

The root account The adminstrator account on a Linux system is called 'root' You need it to install new software

Usefull linux commands commanddescription pwdPrint the name of the current directory lsshow the files in a directory manOpen the manual page for a certain command cdChange directory fileExamine a file morePrint the contents of a text file (try also ‘less’) perlRun a perl script psList the running processes topList the active processes, updating killTerminate a process, try also 'pkill' and 'kill -9'

and more... commanddescription exitClose the current shell (also ctrl+d) sshOpen a connection to a remote computer cpCopy a file to a new location mvMove a file to a new location (or rename a file) rmRemove/delete a file mkdirCreate a new directory rmdirRemove a directory echoPrint a text findFind a file grepFind a text in one or more files

and even more... commanddescription screenstart a virtual terminal, if you want to switch off PC scpsecure network copy catprint the contents of a file to the terminal watchmonitor the output of a shell command tailprint the last lines of a text file, continuously headprint the first lines of a text file tarcreate of read a tarball archive gzipzip a file, use gunzip to unzip dateprint current date/time lncreate a (soft) link to a file, like a shortcut

... commanddescription suswitch to another user, default is 'root' sudoact as another user, password required zypperinstall new software, other flavours: apt-get, yum rebootreboot Linux shutdownshutdown the Linux environment printenvprint the environment variables setenvset the environment variables, depends on shell passwdchange your password