Because most of the host computers on the Internet are Unix-based, it is important to understand the Unix commands and file structure before using the Internet.
In order to type Unix commands, you must have a Unix prompt such as Bourne or C shell. The prompt will generally look like a greater-than symbol (>) or a percent symbol (%). Simply type the desired command at this Unix prompt.
Unlike most desktop computers, Unix is "case sensitive" -- it makes a difference whether you use capital letters or lower-case letters. Almost all Unix commands will be in lower-case letters. Occasionally a filename or a directory will have a capital letter in it. If you see a capital letter, be sure to capitalize theletter (but only that letter).
Launching Applications
To launch an application (make it run), you simply type the name of the application. To launch gopher, you type gopher at the prompt. To launch archie, you type archie at the prompt. And to launch telnet, you type telnet at the prompt.
File Structure
The file structure on Unix machines is very similar to a PC (DOS) machine. If these concepts are not familiar to you, you should probably study a beginner's computer guide before trying to do much with the Internet. An excellent book is Understanding UNIX published by Sybex.
Directories and subdirectories are separated by a front slash (/) -- unlike MS-DOS which uses a backslash (\). Filenames in Unix can be up to 100 characters long and may contain punctuation marks -- unlike MS-DOS filenames which can be up to 11 characters long with a period between the 8th and 9th character.
Common Directory Commands
Command
cd change directory
cd .. change directory back up
one directory (to the parent
directory)
mkdir make directory
rmdir remove directory
ls list the contents of a
directory (similar to dir
in MS-DOS)
ls filename list only filename's
information
ls -a list all information about
the contents of a directory
ls -l list a long listing
(giving owner, attributes,
size, date, time, etc.)
File Commands
Command Explanation/Usage
cp copy a file to another
directory on the same
host computer. Usage:
cp filename directory
mv move a file to another
directory on the same
host computer. The
mv command is also
used to rename a file.
Usage:
mv filename directory
or
mv filename newfilename
rm remove a file. Usage:
rm filename
cat filename display the contents
of a text file named
filename (similar to
type in MS-DOS)
more filename
display the contents of a
text file named filename
but displays the file one
screen at a time (similar to
type |more in MS-DOS)
When using more to display a file:
<space> display the next screen of
text
<Enter> display the next line of text
/ string search forward for the given
string
h help
q quit the display and return to the Unix prompt
