menu "Shells"
-INSERT
-
-config ASH
- bool "ash"
- default y
- depends on !NOMMU
- help
- Tha 'ash' shell adds about 60k in the default configuration and is
- the most complete and most pedantically correct shell included with
- busybox. This shell is actually a derivative of the Debian 'dash'
- shell (by Herbert Xu), which was created by porting the 'ash' shell
- (written by Kenneth Almquist) from NetBSD.
-
-config ASH_BASH_COMPAT
- bool "bash-compatible extensions"
- default y
- depends on ASH
- help
- Enable bash-compatible extensions.
-
-config ASH_JOB_CONTROL
- bool "Job control"
- default y
- depends on ASH
- help
- Enable job control in the ash shell.
-
-config ASH_ALIAS
- bool "alias support"
- default y
- depends on ASH
- help
- Enable alias support in the ash shell.
-
-config ASH_GETOPTS
- bool "Builtin getopt to parse positional parameters"
- default y
- depends on ASH
- help
- Enable getopts builtin in the ash shell.
-
-config ASH_BUILTIN_ECHO
- bool "Builtin version of 'echo'"
- default y
- depends on ASH
- help
- Enable support for echo, builtin to ash.
-
-config ASH_BUILTIN_PRINTF
- bool "Builtin version of 'printf'"
- default y
- depends on ASH
- help
- Enable support for printf, builtin to ash.
-
-config ASH_BUILTIN_TEST
- bool "Builtin version of 'test'"
- default y
- depends on ASH
- help
- Enable support for test, builtin to ash.
-
-config ASH_CMDCMD
- bool "'command' command to override shell builtins"
- default y
- depends on ASH
- help
- Enable support for the ash 'command' builtin, which allows
- you to run the specified command with the specified arguments,
- even when there is an ash builtin command with the same name.
-
-config ASH_MAIL
- bool "Check for new mail on interactive shells"
- default n
- depends on ASH
- help
- Enable "check for new mail" in the ash shell.
-
-config ASH_OPTIMIZE_FOR_SIZE
- bool "Optimize for size instead of speed"
- default y
- depends on ASH
- help
- Compile ash for reduced size at the price of speed.
-
-config ASH_RANDOM_SUPPORT
- bool "Pseudorandom generator and $RANDOM variable"
- default y
- depends on ASH
- help
- Enable pseudorandom generator and dynamic variable "$RANDOM".
- Each read of "$RANDOM" will generate a new pseudorandom value.
- You can reset the generator by using a specified start value.
- After "unset RANDOM" the generator will switch off and this
- variable will no longer have special treatment.
-
-config ASH_EXPAND_PRMT
- bool "Expand prompt string"
- default y
- depends on ASH
- help
- "PS#" may contain volatile content, such as backquote commands.
- This option recreates the prompt string from the environment
- variable each time it is displayed.
-
choice
prompt "Choose which shell is aliased to 'sh' name"
- default FEATURE_SH_IS_ASH
+ 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 FEATURE_SH_IS_ASH
- depends on ASH
- bool "ash"
+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 FEATURE_SH_IS_HUSH
- depends on HUSH
+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 FEATURE_SH_IS_NONE
+config SH_IS_NONE
bool "none"
endchoice
choice
prompt "Choose which shell is aliased to 'bash' name"
- default FEATURE_BASH_IS_NONE
+ 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.
+ 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
can't be used for running them because it won't recongnize
"bash" as a supported applet name.
-config FEATURE_BASH_IS_ASH
- depends on ASH
- bool "ash"
+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 FEATURE_BASH_IS_HUSH
- depends on HUSH
+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 FEATURE_BASH_IS_NONE
+config BASH_IS_NONE
bool "none"
endchoice
-config LASH
- bool "lash (deprecated: aliased to hush)"
- default n
- select HUSH
- help
- lash is deprecated and will be removed, please migrate to hush.
-
-config MSH
- bool "msh (deprecated: please use hush)"
- default n
- select HUSH
- help
- msh is deprecated and will be removed, please migrate to hush.
- If there is a feature msh has but hush does not, please let us know.
+INSERT
-# The minix shell (adds just 30k) is quite complete and handles things
-# like for/do/done, case/esac and all the things you expect a Bourne
-# shell to do. It is not always pedantically correct about Bourne
-# shell grammar (try running the shell testscript "tests/sh.testcases"
-# on it and compare vs bash) but for most things it works quite well.
-# It uses only vfork, so it can be used on uClinux systems.
+comment "Options common to all shells"
+if ASH || HUSH || SH_IS_ASH || BASH_IS_ASH || SH_IS_HUSH || BASH_IS_HUSH
-config SH_MATH_SUPPORT
+config FEATURE_SH_MATH
bool "POSIX math support"
default y
- depends on ASH || HUSH
+ 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 SH_MATH_SUPPORT_64
+config FEATURE_SH_MATH_64
bool "Extend POSIX math support to 64 bit"
default y
- depends on SH_MATH_SUPPORT
+ 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.
config FEATURE_SH_EXTRA_QUIET
bool "Hide message on interactive shell startup"
default y
- depends on HUSH || ASH
+ 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 (HUSH || ASH) && FEATURE_PREFER_APPLETS
+ 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
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. Some selected applets ("NOFORK" applets)
- can even be executed without creating new process.
- Instead, busybox will call <applet>_main() internally.
+ with right parameters.
- However, this causes problems in chroot jails without mounted /proc
- and with ps/top (command name can be shown as 'exe' for applets
- started this way).
-# untrue?
-# Note that this will *also* cause applets to take precedence
-# over shell builtins of the same name. So turning this on will
-# eliminate any performance gained by turning on the builtin "echo"
-# and "test" commands in ash.
-# untrue?
-# Note that when using this option, the shell will attempt to directly
-# run '/bin/busybox'. If you do not have the busybox binary sitting in
-# that exact location with that exact name, this option will not work at
-# all.
+ 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 (HUSH || ASH) && FEATURE_PREFER_APPLETS
+ depends on ASH || HUSH || SH_IS_ASH || BASH_IS_ASH || SH_IS_HUSH || BASH_IS_HUSH
help
- This option causes busybox shells [currently only ash]
- to not execute typical fork/exec/wait sequence, but call <applet>_main
- directly, if possible. (Sometimes it is not possible: for example,
+ 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
This may significantly speed up some shell scripts.
- This feature is relatively new. Use with care.
+ This feature is relatively new. Use with care. Report bugs
+ to project mailing list.
-config CTTYHACK
- bool "cttyhack"
+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
- One common problem reported on the mailing list is "can't access tty;
- job control turned off" error message which typically appears when
- one tries to use shell with stdin/stdout opened to /dev/console.
- This device is special - it cannot be a controlling tty.
-
- Proper solution is to use correct device instead of /dev/console.
-
- cttyhack provides "quick and dirty" solution to this problem.
- It analyzes stdin with various ioctls, trying to determine whether
- it is a /dev/ttyN or /dev/ttySN (virtual terminal or serial line).
- If it detects one, it closes stdin/out/err and reopens that device.
- Then it executes given program. Opening the device will make
- that device a controlling tty. This may require cttyhack
- to be a session leader.
-
- Example for /etc/inittab (for busybox init):
-
- ::respawn:/bin/cttyhack /bin/sh
-
- Giving controlling tty to shell running with PID 1:
-
- $ exec cttyhack sh
-
- Starting an interactive shell from boot shell script:
+ 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.
- setsid cttyhack sh
+endif # Options common to all shells
endmenu