-n disable the name; otherwise, names are by default enabled.
-f means to load the new builtin command name from shared object filename, on systems that support dynamic loading.
-d will delete a builtin previously loaded with -f.
-p alon with a and s print a list of shell builtins. See list
Return value
The return value is 0 unless a name is not a shell builtin or there is an
error loading a new builtin from a shared object.
Management
Enable
For example, to use the test binary found via the PATH
instead of the shell builtin version, run enable -n test.
Disable
Disabling a builtin allows a disk command which has the same name as a shell builtin
to be executed without specifying a full pathname, even though
the shell normally searches for builtins before disk commands.
List
If no name arguments are given, or if the -p option is supplied, a list of shell builtins is printed.
With no other option arguments, the list consists of all enabled shell builtins.
If -n is supplied, only disabled builtins are printed.
If -a is supplied, the list printed includes all builtins, with an indication of whether or not each is enabled.
If -s is supplied, the output is restricted to the POSIX special builtins.