shell/Config.src

#
# For a description of the syntax of this configuration file,
# see scripts/kbuild/config-language.txt.
#

menu "Shells"


choice
	prompt "Choose which shell is aliased to 'sh' name"
	default SH_IS_ASH
	help
	  Choose which shell you want to be executed by 'sh' alias.
	  The ash shell is the most bash compatible and full featured one.

# note: cannot use "select ASH" here, it breaks "make allnoconfig"
config SH_IS_ASH
	depends on !NOMMU
	bool "ash"
	help
	  Choose ash to be the shell executed by 'sh' name.
	  The ash code will be built into busybox. If you don't select
	  "ash" choice (CONFIG_ASH), this shell may only be invoked by
	  the name 'sh' (and not 'ash').

config SH_IS_HUSH
	bool "hush"
	help
	  Choose hush to be the shell executed by 'sh' name.
	  The hush code will be built into busybox. If you don't select
	  "hush" choice (CONFIG_HUSH), this shell may only be invoked by
	  the name 'sh' (and not 'hush').

config SH_IS_NONE
	bool "none"

endchoice

choice
	prompt "Choose which shell is aliased to 'bash' name"
	default BASH_IS_NONE
	help
	  Choose which shell you want to be executed by 'bash' alias.
	  The ash shell is the most bash compatible and full featured one,
	  although compatibility is far from being complete.

	  Note that selecting this option does not switch on any bash
	  compatibility code. It merely makes it possible to install
	  /bin/bash (sym)link and run scripts which start with
	  #!/bin/bash line.

	  Many systems use it in scripts which use bash-specific features,
	  even simple ones like $RANDOM. Without this option, busybox
	  can't be used for running them because it won't recongnize
	  "bash" as a supported applet name.

config BASH_IS_ASH
	depends on !NOMMU
	bool "ash"
	help
	  Choose ash to be the shell executed by 'bash' name.
	  The ash code will be built into busybox. If you don't select
	  "ash" choice (CONFIG_ASH), this shell may only be invoked by
	  the name 'bash' (and not 'ash').

config BASH_IS_HUSH
	bool "hush"
	help
	  Choose hush to be the shell executed by 'bash' name.
	  The hush code will be built into busybox. If you don't select
	  "hush" choice (CONFIG_HUSH), this shell may only be invoked by
	  the name 'bash' (and not 'hush').

config BASH_IS_NONE
	bool "none"

endchoice


INSERT


comment "Options common to all shells"
if ASH || HUSH || SH_IS_ASH || BASH_IS_ASH || SH_IS_HUSH || BASH_IS_HUSH

config FEATURE_SH_MATH
	bool "POSIX math support"
	default y
	depends on ASH || HUSH || SH_IS_ASH || BASH_IS_ASH || SH_IS_HUSH || BASH_IS_HUSH
	help
	  Enable math support in the shell via $((...)) syntax.

config FEATURE_SH_MATH_64
	bool "Extend POSIX math support to 64 bit"
	default y
	depends on FEATURE_SH_MATH
	help
	  Enable 64-bit math support in the shell. This will make the shell
	  slightly larger, but will allow computation with very large numbers.
	  This is not in POSIX, so do not rely on this in portable code.

config FEATURE_SH_EXTRA_QUIET
	bool "Hide message on interactive shell startup"
	default y
	depends on ASH || HUSH || SH_IS_ASH || BASH_IS_ASH || SH_IS_HUSH || BASH_IS_HUSH
	help
	  Remove the busybox introduction when starting a shell.

config FEATURE_SH_STANDALONE
	bool "Standalone shell"
	default n
	depends on ASH || HUSH || SH_IS_ASH || BASH_IS_ASH || SH_IS_HUSH || BASH_IS_HUSH
	help
	  This option causes busybox shells to use busybox applets
	  in preference to executables in the PATH whenever possible. For
	  example, entering the command 'ifconfig' into the shell would cause
	  busybox to use the ifconfig busybox applet. Specifying the fully
	  qualified executable name, such as '/sbin/ifconfig' will still
	  execute the /sbin/ifconfig executable on the filesystem. This option
	  is generally used when creating a statically linked version of busybox
	  for use as a rescue shell, in the event that you screw up your system.

	  This is implemented by re-execing /proc/self/exe (typically)
	  with right parameters.

	  However, there are drawbacks: it is problematic in chroot jails
	  without mounted /proc, and ps/top may show command name as 'exe'
	  for applets started this way.

config FEATURE_SH_NOFORK
	bool "Run 'nofork' applets directly"
	default n
	depends on ASH || HUSH || SH_IS_ASH || BASH_IS_ASH || SH_IS_HUSH || BASH_IS_HUSH
	help
	  This option causes busybox shells to not execute typical
	  fork/exec/wait sequence, but call <applet>_main directly,
	  if possible. (Sometimes it is not possible: for example,
	  this is not possible in pipes).

	  This will be done only for some applets (those which are marked
	  NOFORK in include/applets.h).

	  This may significantly speed up some shell scripts.

	  This feature is relatively new. Use with care. Report bugs
	  to project mailing list.

config FEATURE_SH_HISTFILESIZE
	bool "Use $HISTFILESIZE"
	default y
	depends on ASH || HUSH || SH_IS_ASH || BASH_IS_ASH || SH_IS_HUSH || BASH_IS_HUSH
	help
	  This option makes busybox shells to use $HISTFILESIZE variable
	  to set shell history size. Note that its max value is capped
	  by "History size" setting in library tuning section.

endif # Options common to all shells

endmenu