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# DO NOT EDIT. This file is generated from Config.src
#
# For a description of the syntax of this configuration file,
# see scripts/kbuild/config-language.txt.
#
menu "Shells"
config BUSYBOX_CONFIG_ASH
bool "ash"
default BUSYBOX_DEFAULT_ASH
depends on !BUSYBOX_CONFIG_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 BUSYBOX_CONFIG_ASH_BASH_COMPAT
bool "bash-compatible extensions"
default BUSYBOX_DEFAULT_ASH_BASH_COMPAT
depends on BUSYBOX_CONFIG_ASH
help
Enable bash-compatible extensions.
config BUSYBOX_CONFIG_ASH_IDLE_TIMEOUT
bool "Idle timeout variable"
default BUSYBOX_DEFAULT_ASH_IDLE_TIMEOUT
depends on BUSYBOX_CONFIG_ASH
help
Enables bash-like auto-logout after $TMOUT seconds of idle time.
config BUSYBOX_CONFIG_ASH_JOB_CONTROL
bool "Job control"
default BUSYBOX_DEFAULT_ASH_JOB_CONTROL
depends on BUSYBOX_CONFIG_ASH
help
Enable job control in the ash shell.
config BUSYBOX_CONFIG_ASH_ALIAS
bool "Alias support"
default BUSYBOX_DEFAULT_ASH_ALIAS
depends on BUSYBOX_CONFIG_ASH
help
Enable alias support in the ash shell.
config BUSYBOX_CONFIG_ASH_GETOPTS
bool "Builtin getopt to parse positional parameters"
default BUSYBOX_DEFAULT_ASH_GETOPTS
depends on BUSYBOX_CONFIG_ASH
help
Enable support for getopts builtin in ash.
config BUSYBOX_CONFIG_ASH_BUILTIN_ECHO
bool "Builtin version of 'echo'"
default BUSYBOX_DEFAULT_ASH_BUILTIN_ECHO
depends on BUSYBOX_CONFIG_ASH
help
Enable support for echo builtin in ash.
config BUSYBOX_CONFIG_ASH_BUILTIN_PRINTF
bool "Builtin version of 'printf'"
default BUSYBOX_DEFAULT_ASH_BUILTIN_PRINTF
depends on BUSYBOX_CONFIG_ASH
help
Enable support for printf builtin in ash.
config BUSYBOX_CONFIG_ASH_BUILTIN_TEST
bool "Builtin version of 'test'"
default BUSYBOX_DEFAULT_ASH_BUILTIN_TEST
depends on BUSYBOX_CONFIG_ASH
help
Enable support for test builtin in ash.
config BUSYBOX_CONFIG_ASH_HELP
bool "help builtin"
default BUSYBOX_DEFAULT_ASH_HELP
depends on BUSYBOX_CONFIG_ASH
help
Enable help builtin in ash.
config BUSYBOX_CONFIG_ASH_CMDCMD
bool "'command' command to override shell builtins"
default BUSYBOX_DEFAULT_ASH_CMDCMD
depends on BUSYBOX_CONFIG_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 BUSYBOX_CONFIG_ASH_MAIL
bool "Check for new mail on interactive shells"
default BUSYBOX_DEFAULT_ASH_MAIL
depends on BUSYBOX_CONFIG_ASH
help
Enable "check for new mail" function in the ash shell.
config BUSYBOX_CONFIG_ASH_OPTIMIZE_FOR_SIZE
bool "Optimize for size instead of speed"
default BUSYBOX_DEFAULT_ASH_OPTIMIZE_FOR_SIZE
depends on BUSYBOX_CONFIG_ASH
help
Compile ash for reduced size at the price of speed.
config BUSYBOX_CONFIG_ASH_RANDOM_SUPPORT
bool "Pseudorandom generator and $RANDOM variable"
default BUSYBOX_DEFAULT_ASH_RANDOM_SUPPORT
depends on BUSYBOX_CONFIG_ASH
help
Enable pseudorandom generator and dynamic variable "$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 BUSYBOX_CONFIG_ASH_EXPAND_PRMT
bool "Expand prompt string"
default BUSYBOX_DEFAULT_ASH_EXPAND_PRMT
depends on BUSYBOX_CONFIG_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.
config BUSYBOX_CONFIG_CTTYHACK
bool "cttyhack"
default BUSYBOX_DEFAULT_CTTYHACK
help
One common problem reported on the mailing list is the "can't
access tty; job control turned off" error message, which typically
appears when one tries to use a shell with stdin/stdout on
/dev/console.
This device is special - it cannot be a controlling tty.
The proper solution is to use the correct device instead of
/dev/console.
cttyhack provides a "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).
On Linux it also checks sysfs for a pointer to the active console.
If cttyhack is able to find the real console device, it closes
stdin/out/err and reopens that device.
Then it executes the 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
Starting an interactive shell from boot shell script:
setsid cttyhack sh
Giving controlling tty to shell running with PID 1:
# exec cttyhack sh
Without cttyhack, you need to know exact tty name,
and do something like this:
# exec setsid sh -c 'exec sh </dev/tty1 >/dev/tty1 2>&1'
Starting getty on a controlling tty from a shell script:
# getty 115200 $(cttyhack)
config BUSYBOX_CONFIG_HUSH
bool "hush"
default BUSYBOX_DEFAULT_HUSH
help
hush is a small shell (25k). It handles the normal flow control
constructs such as if/then/elif/else/fi, for/in/do/done, while loops,
case/esac. Redirections, here documents, $((arithmetic))
and functions are supported.
It will compile and work on no-mmu systems.
It does not handle select, aliases, tilde expansion,
&>file and >&file redirection of stdout+stderr.
config BUSYBOX_CONFIG_HUSH_BASH_COMPAT
bool "bash-compatible extensions"
default BUSYBOX_DEFAULT_HUSH_BASH_COMPAT
depends on BUSYBOX_CONFIG_HUSH
help
Enable bash-compatible extensions.
config BUSYBOX_CONFIG_HUSH_BRACE_EXPANSION
bool "Brace expansion"
default BUSYBOX_DEFAULT_HUSH_BRACE_EXPANSION
depends on BUSYBOX_CONFIG_HUSH_BASH_COMPAT
help
Enable {abc,def} extension.
config BUSYBOX_CONFIG_HUSH_HELP
bool "help builtin"
default BUSYBOX_DEFAULT_HUSH_HELP
depends on BUSYBOX_CONFIG_HUSH
help
Enable help builtin in hush. Code size + ~1 kbyte.
config BUSYBOX_CONFIG_HUSH_INTERACTIVE
bool "Interactive mode"
default BUSYBOX_DEFAULT_HUSH_INTERACTIVE
depends on BUSYBOX_CONFIG_HUSH
help
Enable interactive mode (prompt and command editing).
Without this, hush simply reads and executes commands
from stdin just like a shell script from a file.
No prompt, no PS1/PS2 magic shell variables.
config BUSYBOX_CONFIG_HUSH_SAVEHISTORY
bool "Save command history to .hush_history"
default BUSYBOX_DEFAULT_HUSH_SAVEHISTORY
depends on BUSYBOX_CONFIG_HUSH_INTERACTIVE && BUSYBOX_CONFIG_FEATURE_EDITING_SAVEHISTORY
help
Enable history saving in hush.
config BUSYBOX_CONFIG_HUSH_JOB
bool "Job control"
default BUSYBOX_DEFAULT_HUSH_JOB
depends on BUSYBOX_CONFIG_HUSH_INTERACTIVE
help
Enable job control: Ctrl-Z backgrounds, Ctrl-C interrupts current
command (not entire shell), fg/bg builtins work. Without this option,
"cmd &" still works by simply spawning a process and immediately
prompting for next command (or executing next command in a script),
but no separate process group is formed.
config BUSYBOX_CONFIG_HUSH_TICK
bool "Process substitution"
default BUSYBOX_DEFAULT_HUSH_TICK
depends on BUSYBOX_CONFIG_HUSH
help
Enable process substitution `command` and $(command) in hush.
config BUSYBOX_CONFIG_HUSH_IF
bool "Support if/then/elif/else/fi"
default BUSYBOX_DEFAULT_HUSH_IF
depends on BUSYBOX_CONFIG_HUSH
help
Enable if/then/elif/else/fi in hush.
config BUSYBOX_CONFIG_HUSH_LOOPS
bool "Support for, while and until loops"
default BUSYBOX_DEFAULT_HUSH_LOOPS
depends on BUSYBOX_CONFIG_HUSH
help
Enable for, while and until loops in hush.
config BUSYBOX_CONFIG_HUSH_CASE
bool "Support case ... esac statement"
default BUSYBOX_DEFAULT_HUSH_CASE
depends on BUSYBOX_CONFIG_HUSH
help
Enable case ... esac statement in hush. +400 bytes.
config BUSYBOX_CONFIG_HUSH_FUNCTIONS
bool "Support funcname() { commands; } syntax"
default BUSYBOX_DEFAULT_HUSH_FUNCTIONS
depends on BUSYBOX_CONFIG_HUSH
help
Enable support for shell functions in hush. +800 bytes.
config BUSYBOX_CONFIG_HUSH_LOCAL
bool "Support local builtin"
default BUSYBOX_DEFAULT_HUSH_LOCAL
depends on BUSYBOX_CONFIG_HUSH_FUNCTIONS
help
Enable support for local variables in functions.
config BUSYBOX_CONFIG_HUSH_RANDOM_SUPPORT
bool "Pseudorandom generator and $RANDOM variable"
default BUSYBOX_DEFAULT_HUSH_RANDOM_SUPPORT
depends on BUSYBOX_CONFIG_HUSH
help
Enable pseudorandom generator and dynamic variable "$RANDOM".
Each read of "$RANDOM" will generate a new pseudorandom value.
config BUSYBOX_CONFIG_HUSH_EXPORT_N
bool "Support 'export -n' option"
default BUSYBOX_DEFAULT_HUSH_EXPORT_N
depends on BUSYBOX_CONFIG_HUSH
help
export -n unexports variables. It is a bash extension.
config BUSYBOX_CONFIG_HUSH_MODE_X
bool "Support 'hush -x' option and 'set -x' command"
default BUSYBOX_DEFAULT_HUSH_MODE_X
depends on BUSYBOX_CONFIG_HUSH
help
This instructs hush to print commands before execution.
Adds ~300 bytes.
config BUSYBOX_CONFIG_MSH
bool "msh (deprecated: aliased to hush)"
default BUSYBOX_DEFAULT_MSH
select BUSYBOX_CONFIG_HUSH
help
msh is deprecated and will be removed, please migrate to hush.
choice
prompt "Choose which shell is aliased to 'sh' name"
default BUSYBOX_CONFIG_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 BUSYBOX_CONFIG_FEATURE_SH_IS_ASH
depends on BUSYBOX_CONFIG_ASH
bool "ash"
depends on !BUSYBOX_CONFIG_NOMMU
config BUSYBOX_CONFIG_FEATURE_SH_IS_HUSH
depends on BUSYBOX_CONFIG_HUSH
bool "hush"
config BUSYBOX_CONFIG_FEATURE_SH_IS_NONE
bool "none"
endchoice
choice
prompt "Choose which shell is aliased to 'bash' name"
default BUSYBOX_CONFIG_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 BUSYBOX_CONFIG_FEATURE_BASH_IS_ASH
depends on BUSYBOX_CONFIG_ASH
bool "ash"
depends on !BUSYBOX_CONFIG_NOMMU
config BUSYBOX_CONFIG_FEATURE_BASH_IS_HUSH
depends on BUSYBOX_CONFIG_HUSH
bool "hush"
config BUSYBOX_CONFIG_FEATURE_BASH_IS_NONE
bool "none"
endchoice
config BUSYBOX_CONFIG_SH_MATH_SUPPORT
bool "POSIX math support"
default BUSYBOX_DEFAULT_SH_MATH_SUPPORT
depends on BUSYBOX_CONFIG_ASH || BUSYBOX_CONFIG_HUSH
help
Enable math support in the shell via $((...)) syntax.
config BUSYBOX_CONFIG_SH_MATH_SUPPORT_64
bool "Extend POSIX math support to 64 bit"
default BUSYBOX_DEFAULT_SH_MATH_SUPPORT_64
depends on BUSYBOX_CONFIG_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 BUSYBOX_CONFIG_FEATURE_SH_EXTRA_QUIET
bool "Hide message on interactive shell startup"
default BUSYBOX_DEFAULT_FEATURE_SH_EXTRA_QUIET
depends on BUSYBOX_CONFIG_HUSH || BUSYBOX_CONFIG_ASH
help
Remove the busybox introduction when starting a shell.
config BUSYBOX_CONFIG_FEATURE_SH_STANDALONE
bool "Standalone shell"
default BUSYBOX_DEFAULT_FEATURE_SH_STANDALONE
depends on (BUSYBOX_CONFIG_HUSH || BUSYBOX_CONFIG_ASH) && BUSYBOX_CONFIG_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 BUSYBOX_CONFIG_FEATURE_SH_NOFORK
bool "Run 'nofork' applets directly"
default BUSYBOX_DEFAULT_FEATURE_SH_NOFORK
depends on (BUSYBOX_CONFIG_HUSH || BUSYBOX_CONFIG_ASH) && BUSYBOX_CONFIG_FEATURE_PREFER_APPLETS
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 BUSYBOX_CONFIG_FEATURE_SH_HISTFILESIZE
bool "Use $HISTFILESIZE"
default BUSYBOX_DEFAULT_FEATURE_SH_HISTFILESIZE
depends on BUSYBOX_CONFIG_HUSH || BUSYBOX_CONFIG_ASH
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.
endmenu
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