Chapter 7 Study Guide

Command input and output

Bash Shell Responsible for providing user interface

Interprets commands entered on command line

Can manipulate command input and output

Input and Outputs of commands Represented by labels know as file descriptors. There are 3 file descriptors:

Standard input (stdin) information processed by the command during execution

Standard output (stdout) refers to the normal output of a command

Standard error (stderr) refers to any error messages generated by the command

Both stdout and stderr are displayed on the terminal screen by default

Use the BASH shell to redirect stdout and stderr from the terminal screen to a file on filesystem

Use the > shell metacharacter followed by absolute or relative pathname of the file

ls /etc/hosts /etc/h 1>goodoutput

Use the < to redirect a file to the stdin

cat </etc/issue