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#
# For a description of the syntax of this configuration file,
# see scripts/kbuild/config-language.txt.
#
menu "Shells"
INSERT
choice
prompt "Choose which shell is aliased to 'sh' name"
default FEATURE_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"
depends on !NOMMU
config FEATURE_SH_IS_HUSH
depends on HUSH
bool "hush"
config FEATURE_SH_IS_NONE
bool "none"
endchoice
choice
prompt "Choose which shell is aliased to 'bash' name"
default FEATURE_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.
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 FEATURE_BASH_IS_ASH
depends on ASH
bool "ash"
depends on !NOMMU
config FEATURE_BASH_IS_HUSH
depends on HUSH
bool "hush"
config FEATURE_BASH_IS_NONE
bool "none"
endchoice
config SH_MATH_SUPPORT
bool "POSIX math support"
default y
depends on ASH || HUSH
help
Enable math support in the shell via $((...)) syntax.
config SH_MATH_SUPPORT_64
bool "Extend POSIX math support to 64 bit"
default y
depends on SH_MATH_SUPPORT
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 HUSH || ASH
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
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. Some selected applets ("NOFORK" applets)
can even be executed without creating new process.
Instead, busybox will call <applet>_main() internally.
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.
config FEATURE_SH_NOFORK
bool "Run 'nofork' applets directly"
default n
depends on (HUSH || ASH) && FEATURE_PREFER_APPLETS
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 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.
endmenu
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