# The shopt builtin command

The `shopt` builtin manages [shell options](../../internals/shell_options.md), a
set of boolean (`on`/`off`) configuration variables that control the
behaviour of the shell.

## Synopsis

    shopt [-pqsu] [-o] <OPTNAME...>

## Description

Note: Some of these options and other shell options can also be set with
[the set builtin](../../commands/builtin/set.md).

### Options

  Option   Description
  -------- -----------------------------------------------------------------------------------------------------------------------------
  `-o`     Restrict the values of `<OPTNAME...>` to only those also known by [the set builtin](../../commands/builtin/set.md)
  `-p`     Print all shell options and their current value. **Default**.
  `-q`     Quiet mode. Set exit code if named option is set. For multiple options: `TRUE` if all options are set, `FALSE` otherwise
  `-s`     Enable ([s]{.underline}et) the shell options named by `<OPTNAME...>` or list all *enabled* options if no names are given
  `-u`     Disabe ([u]{.underline}nset) the shell options named by `<OPTNAME...>` or list all *disabled* options if no names are given

As noted above, if only `-s` or `-u` are given without any option names,
only the currently enabled (`-s`) or disabled (`-u`) options are
printed.

### Exit code

When listing options, the exit code is `TRUE` (0), if all options are
enabled, `FALSE` otherwise.

When setting/unsetting an option, the exit code is `TRUE` unless the
named option doesn't exitst.

## Examples

Enable the `nullglob` option:

    shopt -s nullglob

## Portability considerations

The `shopt` command is not portable accross different shells.

## See also

-   Internal: [The set builtin command](../../commands/builtin/set.md)
-   Internal: [List of shell options](../../internals/shell_options.md)