bash built ins

A builtin is a utility (also called a command) that is built into a shell. Each of the
shells has its own set of builtins. When it runs a builtin, the shell does not fork a
new process. Consequently builtins run more quickly and can affect the environ-
ment of the current shell. Because builtins are used in the same way as utilities, you
will not typically be aware of whether a utility is built into the shell or is a stand-
alone utility.The echo utility is a shell builtin. The shell always executes a shell builtin before trying to find a command or utility with the same name.


Listing bash builtins

To get a complete list of bash builtins, give the command info bash builtin. To display a page with more information on each builtin, move the cursor to one of the lines listing a builtin command and press RETURN. Alternatively, after typing info bash, give the command /builtin to search the bash documentation for the string builtin. The cursor will rest on the word Builtin in a menu; press RETURN to display the builtins menu.