The Shell

- The shell is a text-based user interface that allows for the user to enter commands for a resulting on screen print - SSH, or a secure shell, is actually not a shell at all. It is the communication protocol. The actual shell is running on the Unix host.

An operating system is a seed, a Kernel is its core, and the Shell is the outside of this. All the user can view is the shell, because the rest is hidden from the user.

Type	Description
sh	Based on an early shell
bsh	Good for scripting
bash	The bourne again shell
zsh	Based on bash, powerful language
ash	Very Small shell, used for system recovery
ksh	Written by Korn
csh	Scripting language that looks like C
tcsh	Like csh, has automatic command line completion

The fsu system uses tcsh

Logging into your Home Directory

Directories are a hierarchical tree the `~` represents the home directory

The tree has its root at the top with / ("root") directory. It is called this because it is the basis or root of the directory hierarchy.

pwd- Prints the working directory cd- changes the directory

Therefore : cd ~ -changes to the users home directory

To move up in the hierarchy we use ... Therefore : cd ... - ... is a pointer to the next higher directory, so it will change to this.

. on the other hand represents the current directory We can use these in combination to change directories such as: cd ../banking - will move up a directory and search for the banking directory and- cd ../.. will move up and then up again. If the user ends the entry with a slash explicitly (cd ../../) this says the last thing is a string in the directory

Absolute pathnames start with a slash

• specified absolute path is always relative to the root

rmdir only deletes empty directories ls -l - list long

White- Ordinary file (white on a black screen) Blue- Directory Green- Executable file

ls -a - list all

Copy a File

- `cp` means to *"copy this file"*; use this to make a duplicate of a file - Ways to express which file to copy

The form of the copy command is: cp existingFile newFile

To confirm overwriting a file, so we dont lose the data, we use the following -i flag. If the file already exists the user will be told and given the option not to overwrite its contents

The . and .. Directories: mkdir freshDir cd freshDir

the ls -a command means list all. Used ls -al, or "long listing" in order to see the long listing. The display will look like this.

ls -al  
total 8  
drwx------ 2 lockwood CS-Faculty 4096 Feb 24 21:25 .  
drwx--x--x 21 lockwood CS-Faculty 4096 Feb 24 21:25 .

cp ../thatFile . - copy a file from the parent directory to the current directory mv ../thatFile . - move a file from the parent directory to the current directory

Copy the entire directory cp -R ~/myDir/newFileDir/ ~/myOtherDir

• -R means Recursive.

the flag -p preserves files attributes when being copied

Man Pages

- `man` is the Unix instruction manual describing every command - `info` is the GNU augmentation to `man` - `apropos` helps find an appropriate `man` topic

man Describes each Command

• if you need to find details about a command or its flags use: man commandName
• man ls, man cp, man scp

Search commands / - Enter a search term n - Find next entry N - Find a previous entry q - Quit

info was made in order to replace the outdated man pages. info is more like a book about unix instead of a catalog of commands. Many users prefer to use man to describe how to use a command, and man for more detail about a command.

info ls

The `ls' program lists information about files (of any type, including  
directories). Options and file arguments can be intermixed  
arbitrarily, as usual.  
For non-option command-line arguments that are directories, by  
default `ls' lists the contents of directories, not recursively, and  
omitting files with names beginning with `.'. For other non-option  
arguments, by default `ls' lists just the file name. If no non-option  
argument is specified, `ls' operates on the current directory, acting  
as if it had been invoked with a single argument of `.'.  
By default, the output is sorted alphabetically, according to the  
locale settings in effect.(1) If standard output is a terminal, the  
output is in columns (sorted vertically) and control characters are  
output as question marks; otherwise, the output is listed one per line  
and control characters are output as-is.  
--zz-Info: (coreutils.info.gz)ls invocation, 58 lines --Top--------------------------  
Welcome to Info version 4.13. Type h for help, m for menu item

Search command s - Enter a search term } - Find next entry { - Find previous entry q - Quit

apropos searches the man database for a string. If you forget the command to make a directory. You could try:

• apropos make directory
• or apropros "make directory" to search for the entire string

Pine - Email Client

- Unix account comes with an email accoutn - `pine` is an email client from the University of Washington - you can send email attachments through it

To enter pine type pine or alpine To edit the automatic forward file enter: nano ~/.forward