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Output from functions can be redirected to files instead of the screen. For example ’ls > temp’ will take the normal output from the ’ls’ function, and write it into a textfile called ’temp’. Input to functions can be directed into a program. For example ’sort < temp’ will make the file ’temp’ the input to the sort command.

Simple batch files can be created by putting a list of commands in a normal text file. The file can then be made executable using the command ’chmod 755 filename’. The program can then be run using ’./filename’.

2.3 NETWORKING

Networks are a key component of Linux operating systems. Each computer on a network may have a name, such as ’claymore.engineer.gvsu.edu’, but each computer must have a number, such as ’148.61.104.215’. You can log into other Linux and Unix machines with commands such as ‘telnet claymore.engineer.gvsu.edu’, ’telnet 148.61.104.215’ or ‘rlogin claymore.engineer.gvsu.edu’. This allows you to sit at one machine, and use many others, even around the world.

You can also access other computers with public access directories using the ‘ftp’ command. For example try ‘ftp ftp4.netscape.com’. This will connect you to a computer some place in the U.S. When it asks you for your ‘login name’ type ‘anonymous’. When it asks for a ‘password’, enter your name. You may now move around using ls, pwd, cd, etc. If you want to get a file from some directory, type ‘binary’, then type ‘get filename’, or ’get filenames’. ‘quit’ ends everything. If you log into a machine with FTP and you have write permissions you can also write files to the machine using ’put filename’ or ’mput filenames’. If you useFTP to log into a computer that you have account on you will be able to move outside of the limited ftp directories.