Red Hat® Linux® 7 Unleashed

Special Characters

Some characters have special meaning to Linux shells, so using them as part of variable names or strings causes your program to behave incorrectly. If a string contains such characters, you also have to use escape characters (backslashes) to indicate that the special characters should not be treated as special characters. Some of these characters are shown in Table 25.2.

Table 25.2. Special Shell Characters

Character	Explanation
$	Indicates the beginning of a shell variable name
|	Pipes standard output to next command
#	Starts a comment
&	Executes a process in the background
?	Matches one character
*	Matches one or more characters
>	Output redirection operator
<	Input redirection operator
`	Command substitution (the backquote ...