contrl-d -exit  or logoff
 The proper way to shut down in linux:
     1. Become root
     2. sync (data in memory sent to disk)
     3. reboot then enter

cp  -to copy file
  cp <file to be copied> <destination>
  Example:
   cp /etc/passwd /mnt/floppy/password.txt
   cp <path/filename> <destination path/filename>
   >First part of cp or copy command is the directory where the file is:
     Examples: /etc /mnt/floppy /mnt/cdrom
     cp linux~.txt (name on floppy-can't use tilde ~ with linux-so you need to change name)     /home/ck/lcomm.txt 
  This copies text file to this subdirectory and changes the name-same content.

File condensation and manipulation:

gzip -zipped files gunzip -to unzip
tar -tarred files, compressed files 
Examples: mfm1.3.tar.Z freedom_desktop.tar.gz youngcpp.tar 
to unzip a gzipped file (* .tar) or (* .gz) gunzip (filename) gunzip motif.Z 
to untar a tarred file (* .tar) tar-xvf titan(filename)
to both unzip and untar tar -zxvf titan(filename)

ln  -link, soft link or hard link  
      ln [options] source [dest]
      ln [options] source directory
      hard links made by default if no option, switch
     ln -s  -soft link, does not come into play on boot up 
  >Generally speaking, use only soft link only because if hard link fails to work on boot,  then the computer may not boot up.
  >To create a soft link to automatically boot up a program
   Example: To have myslq daemon to automatically run at boot up
     cd /etc/init.d
     ln -s /etc/init.d/mysqld /etc/rc.d/rc3.d/S81mysqld
     ln -s source target destination and program to start. Use capital S to start automatically. Use
any number but must be different from other numbers in other scripts

ls  -list
  switches of ls:
  ls -l  -long names Gives description so you can tell directories from files and other information
  ls -a  -show me all files including hidden files shows dot files which start with period

mount -mount a drive This command generally only needed in older versions of linux
   Examples:
     mount /dev/fa0 mnt/floppy
    To mount floppy
    >Become root and type
     mount /mnt/floppy
    >To see contents of floppy:   ls /mnt/floppy

mv  -move, rename (use with great caution, dangerous command)
   Change file name with mv and move file -powerful command-be careful
   Examples:
     mv <old filename> <new filename>
     mv <path/filename> <newpath/filename>
     mv removes a file or moves it from one directory to another 
     mv -i oldname newname
      mv -I filename directory [/newname]

cat    Use command cat only for viewing short files. Very useful for this purpose.
   cat /etc/hosts

more less  (These are 2 separate commands and very useful ones for viewing text)
   >Use commands to see longer text files in an orderly way: that is, you see one section at a time, then you can go to the next session when viewing text on the command line.
  >Use  the spacebar to go to next section when you view the text file. To end, type q
    more <filename>  more linuxtext (To view contents of file, linuxtext)
    less <filename>    less linuxtext   (To view contents of file, linuxtext)

rm -(remove a filename, file) 
   rm <filename> Will ask you for confirmation
    And switches:
  rm -f Will force delete-won't ask
  rm-r delete all subdirectories and files -powerful command be careful
  rm -fr - " " -will not ask for confirmation
      * means everything like DOS    Example: rm -f *
   rm -i asks you to confirm that you want to delete each file
   rm -i <filename> rm -fr remove, forcible recourse

rpm -package for installing programs.
   >This command applies to Red Hat distribution. Installing-uninstalling RPM-s are are proprietary (only used with Red Hat or related linux distribution like Fedora)  RPM stands for Red Hat Package Manager.
  1. Download using Mozilla web browser or Netscape or ftp. In Netscape, hold down shift key when downloading rpm.
2. Install rpm install /rpm -i- You can save time by typing only 1st 2 letters of name of rpm-then hit tab key.
3. To uninstall use rpm -e <name of file> 
  >How can I install an rpm off of a FTP server?
RPM supports the use of ftp on the command line to update packages. Keep in mind you must have a network connection of some kind for this to work. :-)
  Format:    rpm (options) (pathname)
  Example:
rpm -uvh ftp ://ftp .redhat.com/pub/redhat/redhat-4.0/updates/i386/ghostscript-3.33-3.i386.rpm
 >In general, normal usage of the rpm command can be summarized as follows:
---Installation/Upgrading/Removal
  To install a package: rpm -ivh <filename>
     Example: rpm -ivh somepackage.1.1-4.i386.rpm 
  To upgrade a package: rpm -Uvh <filename>
     Example: rpm -uvh somepackage.1.1-5.i386.rpm 
  To remove a package: rpm -e <packagename>
    Example: rpm -ivh somepackage
  >Also, for upgrading or installing some packages you may need to use additional flags to force the install to happen. It is only recommended to use these if you know why these flags were needed.
   --force -will overwrite files that are owned by other packages.
   --nodeps -will install even if the package needs packages that were not installed. 
---Querying
 >To see if a package is installed:
      Example:  rpm -q <packagename>
      Example: rpm -q <somepackage>
>To get info on an installed package: 
      Example: rpm -qi <packagename>
                     rpm -qi somepackage
>To list which files belong to a package:
    Example: rpm -ql <packagename>
    Example: rpm -ql somepackage
To see what package a file belongs to: rpm -qf <path-to-filename>
ex: rpm -qf /usr/bin/some_executable
>One can usually join various query commands together, so
     rpm -qil 
     -will give information and list all the files in the package.
>To look in a rpm filename that isn't install example, you tag on the p to the query line.
       Example: rpm -qilp somepackage.1.1-4.i386.rpm 
           -will list the information and the files contained in somepackage.
  --Verification 
>To see what files on the system may have changed from their initial settings you can use RPM, to check up on them.
    Example:  rpm -Va 
       -will give you a list of all files that have changed in one form or another since the package it is associated was install ed. This can be a lot of files (and a lot may be changed due to post installation work). To just see what packages have changed so that you can verify them more individually, you can do the following:
   rpm -Va | awk ''{print $2}'' | xargs rpm -qf | sort -u &> /tmp/file1
  Then look in the file /tmp/file1 for which packages have had changes from them.

shell  -terminal which has functionalities communication terminal to communicate with a computer
  >The command interpreter used to pass commands to an operating system; so called because it is the part of the operating system that interfaces with the outside world. 
   .bashrc is the main shell configuration file for a user (there are other shells of course)
      cat .bashrc command to see file
      cat bashrc | more to see file one screen at time
      cat bashrc | less to scroll

man (topic) ex: man gzip -manual, to go to manual To access help files in both unix and linux

Miscellaneous and Summaries of Commands:

  bin -(bin stands for binary and binary files are all executable programs)
 >Ways to look at directory contents:
    1. go to directory with cd >then ls
      2. ls /directory
         Example: ls /mnt ls-l /mnt ls -al lists hidden, long filenames

 ^ up arrow-goes to previous screen
clear -clear screen
 # Use this symbol if you want to comment this out. For your information not for linux to read

>To create directories -Go to where you want the directory to be - or type path:     /mnt/floppy/gofaq.txt use:
   mkdir   (make directory)
   Contrl-d -go back to other available user 
   man -show manual, help files ex: man gzip
   pico -A simple, nice editor Use pico -w  to help prevent mistakes in editing.
   pine - popular email client for command line (text only) Very easy to use.
   gzip gunzip zipped files
  .tar tar -xvf tar zxvf  tarred (a certain file format) files
   startx -start in graphic mode. Important command to remember if you like to switch between runlevels-Go from text only to graphical
   |  (pipe) = The pipe command is a very important command to redirect standard output from one process to another
         Example: dir | more (Take the dir command which shows files in a directory and pipe to more to view in an orderly fashion.)

 root-every directory can have a root -can mean root directory -or the root is superuser. The Unix, linux superuser account (with user name "root" and user ID 0) that overrides all other file permissions. The term avatar is also used. By extension, the privileged system-maintenance login on any operating system.
   su (enter)-to become super user or change to different user
   Cntrl-d -to go back to ck user
 
  cd (and space) will take you back to home directory  
  cd .. Takes you back to prior directory
   Cntrl-d -to go back
   ifconfig -shows interface configuration for network
   Commands To view and analyze Network: 
      lo -loopback-virtual interface Needed for local machine
      etho-o -physical card(network card), hardware address given, recognized in BUS
       The  inet address is the IP address of card
         broadcast address represents a subnet of network addresses
   ls -to list
   ls -l  - to list in long form, this command with switch -l shows permissions for files and directories.
   >In linux, someone owns a file and is the only one who has permission to use the file except for root that has permission to change any file:
   Example: drwxr-xr -x 2 root root bin -d (defines a directory; by group of 3:directory-then permission-user- bin is name of directory

>Linux names for devices:
   cuu -comports
   cui -com interfaces
   fd -floppy drives
   tape -tapes drive
   hd -hard drive

  Users:

 >If you want to see what users exist, here is the command: more /etc/passwd
   This will display the file which contains info about all the users.
   >If you want to add user nick, here's what you do:
     adduser nick (must be root to add user)
     passwd nick -to give password to nick
   >User profile is in  the hidden file .bashrc
     .bashrc -user specified alias and function
     /home/user/.bashrc
     PATH=
   First have to put path you already have.  Note: You have to log out and back in to take effect

Searching and Finding:

    where is -searches anywhere on the computer
    which -searches only in your defined path
    find  -keyword search from where to search
       Example: find / -name -file -number -size -pattern mysql -print  -file
       Example:  find path expression
       Example:  file /etc/init.d/mysqul like right mous click an go to properties
       What is your current path? echo $ PATH
    put  (To add a path)  -use command line or file

Other more advanced linux commands:

   >To see other machines using mount command
         mount 192.168.1.30:/texts 

  >Samba -Samba is a software suite that enable linux machines to communicate with Windows machines. The location is in /etc
      /etc/samba/smb.conf

 >mysql (the database of linux)
   to start the mysql  -database
       Example:  /etc/init.d/mysquld start

>Modules in linux are similar to device drivers in Windows:
  Commands involving modules:
     lsmod -list modules
    modinfo -d (to find information about particular modules)
    insmod   (to load a module)

  To see partions:  fdisk -l

   >Tap up arrow  to bring up previous commands
   >Tap down arrow  to bring forward commands
 
   >Text Editors:
     vi - vi is a complex editor (major learning curve needed so only experts need try)
    pico -Pico is easier editor Always usecommand pico with switch -w
   Example:  pico-w linux text
   - so there won't be wordwrap which could create mistakes
 
  >Commands Listed by Function:

 File manipulation commands:

cat -Concatenate and display a file, for viewing short text file only
chmod -Change the permissions mode of a file warning: dangerous command
chown - Change the owner and/or group of a file  warning: dangerous command
diff - Display differences between pairs of text files
grep - Search a file for a specific text string. Important command used to filter a search
mv  Move or rename a file - warning: dangerous command
rm - Remove a file warning: dangerous command

  Display commands

date - Print the date and time
finger - Display information about a user
head - Display the first few lines of a file
less - Browse a text file
ls - List the contents of a directory
man - Display a reference manual page
     Example: type: man copy to understand copy command To advance each section, use spacebar; to quit, type q
more - Display a text file
pwd - Display the working directory pathname
tail - Display the end of a file
who - Display who is on the system 

Process commands:

exit - Terminate a process
kill - Terminate or send a signal to a process
passwd - Create or change a password
ps - Display the status of a process 
   Example:  ps -ef | grep sendmail  -to see if sendmail is running 
ps -aux -show all processes running

Internet commands:

telnet  (Connect to a remote system using the Telnet protocol, dangerously open)
ssh  (secure shell -secure remote access, much safer)

  >Email: Don't use mail command-this communicates directly with mail daemon 
    mail -checks mail mail <email address> send mail
     -v (switch for verbose) to see what's here
     Can use pico to view  body of email
    pine is a good, simple email program
   daemon is a continuously running program like Windows programs that run in the background.
  cntrl -l check mail with Pine mail program

  >  This symbol is a directing command

> TAB Use tab key to complete command
Use arrow keys:
  ^ Use up arrow to bring up previous command 
 v Use down arrow to go down in history of commands
history -to see history of commands-you can scroll through with up and down arrows

Use Cntl-alt-backspace to get out of GUI quickly

Network commands:

>Use these commands to see your network setup:
  ifconfig-a shows network setup but be careful since ifconfig is also used to configure network setup
    To see network files to determine how network is setup or for network troubleshooting:
      cat /etc/sysconfig/network
      cat /etc/hosts
  netstat (To see status of network)

 ssh  (secure shell) Used like telnet but more secure. You exchange keys.
  ssh is NOT like FTP, It is NOT like telnet. It is "Secure Shell"
  telnet is does NOT run as a daemon. This is why you will not find a PID to kill.
  >Here are the steps to disable Telnet which you should disable unless you want uninvited guests:
   1. Edit the file; /etc/inetd.conf. Comment out (#) the line containing the word "telnet". Save the file
   2. Reboot

More Miscellaneous Notes:

>You can change from one shell to another.
  Try Ctrl-F1, F2, F3, etc
  You should be able to switch shells.

>You first do ps -aux | grep sendmail
  Then you note down the PID number, which is in the first column
 Then you do kill PID#

After you create a user, you have to type: passwd <username>

cat /var/log/messages | more -to see text of file messages

dmesg | less  -to look at boot record, good for troubleshooting

Note: To find more linux information:
Linux CD has "how to" files as documents
http://www.linux.org -has "how to" files