builtin: builtin [shell-builtin [arg ...]]
Execute shell builtins.
Execute SHELL-BUILTIN with arguments ARGs without performing command lookup. This is useful when you wish to reimplement a shell builtin as a shell function, but need to execute the builtin within the function.
Exit Status:
Returns the exit status of SHELL-BUILTIN, or false if SHELL-BUILTIN is
not a shell builtin..