x86: missing kernel symbols

[openwrt.git] / package / busybox / config / shell / Config.in

diff --git a/package/busybox/config/shell/Config.in b/package/busybox/config/shell/Config.in
index b9a1b4d..57f490e 100644 (file)
--- a/package/busybox/config/shell/Config.in
+++ b/package/busybox/config/shell/Config.in
@@ -5,104 +5,68 @@
 
 menu "Shells"
 
 
 menu "Shells"
 

-choice
-       prompt "Choose your default shell"
-       default BUSYBOX_CONFIG_FEATURE_SH_IS_ASH
-       help
-         Choose a shell. The ash shell is the most bash compatible
-         and full featured one.
-
-config BUSYBOX_CONFIG_FEATURE_SH_IS_ASH
-       select BUSYBOX_CONFIG_ASH
-       bool "ash"
-
-config BUSYBOX_CONFIG_FEATURE_SH_IS_HUSH
-       select BUSYBOX_CONFIG_HUSH
-       bool "hush"
-
-config BUSYBOX_CONFIG_FEATURE_SH_IS_LASH
-       select BUSYBOX_CONFIG_LASH
-       bool "lash"
-
-config BUSYBOX_CONFIG_FEATURE_SH_IS_MSH
-       select BUSYBOX_CONFIG_MSH
-       bool "msh"
-
-config BUSYBOX_CONFIG_FEATURE_SH_IS_NONE
-       bool "none"
-
-endchoice
-

 config BUSYBOX_CONFIG_ASH
        bool "ash"
        default y
 config BUSYBOX_CONFIG_ASH
        bool "ash"
        default y

-       select BUSYBOX_CONFIG_TEST
+       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
        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'
+         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.
 
          shell (by Herbert Xu), which was created by porting the 'ash' shell
          (written by Kenneth Almquist) from NetBSD.
 

-comment "Ash Shell Options"
+config BUSYBOX_CONFIG_ASH_BASH_COMPAT
+       bool "bash-compatible extensions"
+       default y

        depends on BUSYBOX_CONFIG_ASH
        depends on BUSYBOX_CONFIG_ASH

+       help
+         Enable bash-compatible extensions.

 
 config BUSYBOX_CONFIG_ASH_JOB_CONTROL
 
 config BUSYBOX_CONFIG_ASH_JOB_CONTROL

-       bool "  Enable Job control"
+       bool "Job control"

        default y
        depends on BUSYBOX_CONFIG_ASH
        help
          Enable job control in the ash shell.
 
        default y
        depends on BUSYBOX_CONFIG_ASH
        help
          Enable job control in the ash shell.
 

-config BUSYBOX_CONFIG_ASH_READ_NCHARS
-       bool "  Enable 'read -n N' and 'read -s' support"
-       default n
+config BUSYBOX_CONFIG_ASH_ALIAS
+       bool "alias support"
+       default y

        depends on BUSYBOX_CONFIG_ASH
        help
        depends on BUSYBOX_CONFIG_ASH
        help

-         'read -n N' will return a value after N characters have been read.
-         'read -s' will read without echoing the user's input.
+         Enable alias support in the ash shell.

 
 

-config BUSYBOX_CONFIG_ASH_READ_TIMEOUT
-       bool "  Enable 'read -t S' support."
+config BUSYBOX_CONFIG_ASH_GETOPTS
+       bool "Builtin getopt to parse positional parameters"

        default y
        depends on BUSYBOX_CONFIG_ASH
        help
        default y
        depends on BUSYBOX_CONFIG_ASH
        help

-         'read -t S' will return a value after S seconds have passed.
-         This implementation will allow fractional seconds, expressed
-         as a decimal fraction, e.g. 'read -t 2.5 foo'.
+         Enable getopts builtin in the ash shell.

 
 

-config BUSYBOX_CONFIG_ASH_ALIAS
-       bool "  Enable alias support"
+config BUSYBOX_CONFIG_ASH_BUILTIN_ECHO
+       bool "Builtin version of 'echo'"

        default y
        depends on BUSYBOX_CONFIG_ASH
        help
        default y
        depends on BUSYBOX_CONFIG_ASH
        help

-         Enable alias support in the ash shell.
+         Enable support for echo, builtin to ash.

 
 

-config BUSYBOX_CONFIG_ASH_MATH_SUPPORT
-       bool "  Enable Posix math support"
+config BUSYBOX_CONFIG_ASH_BUILTIN_PRINTF
+       bool "Builtin version of 'printf'"

        default y
        depends on BUSYBOX_CONFIG_ASH
        help
        default y
        depends on BUSYBOX_CONFIG_ASH
        help

-         Enable math support in the ash shell.
+         Enable support for printf, builtin to ash.

 
 

-config BUSYBOX_CONFIG_ASH_MATH_SUPPORT_64
-       bool "    Extend Posix math support to 64 bit"
-       default n
-       depends on BUSYBOX_CONFIG_ASH_MATH_SUPPORT
-       help
-         Enable 64-bit math support in the ash shell.  This will make
-         the shell slightly larger, but will allow computation with very
-         large numbers.
-
-config BUSYBOX_CONFIG_ASH_GETOPTS
-       bool "  Enable getopts builtin to parse positional parameters"
+config BUSYBOX_CONFIG_ASH_BUILTIN_TEST
+       bool "Builtin version of 'test'"

        default y
        depends on BUSYBOX_CONFIG_ASH
        help
        default y
        depends on BUSYBOX_CONFIG_ASH
        help

-         Enable getopts builtin in the ash shell.
+         Enable support for test, builtin to ash.

 
 config BUSYBOX_CONFIG_ASH_CMDCMD
 
 config BUSYBOX_CONFIG_ASH_CMDCMD

-       bool "  Enable cmdcmd to override shell builtins"
+       bool "'command' command to override shell builtins"

        default y
        depends on BUSYBOX_CONFIG_ASH
        help
        default y
        depends on BUSYBOX_CONFIG_ASH
        help


@@ -110,179 +74,337 @@ config BUSYBOX_CONFIG_ASH_CMDCMD
          you to run the specified command with the specified arguments,
          even when there is an ash builtin command with the same name.
 
          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_BUILTIN_ECHO
-       bool "  Enable builtin version of 'echo'"
-       default y
-       depends on BUSYBOX_CONFIG_ASH
-       help
-         Enable support for echo, built in to ash.
-
-# this entry also appears in coreutils/Config.in, next to the echo applet
-config BUSYBOX_CONFIG_FEATURE_FANCY_ECHO
-       bool "  Enable echo options (-n and -e)"
-       default y
-       depends on BUSYBOX_CONFIG_ASH_BUILTIN_ECHO
-       help
-         This adds options (-n and -e) to echo.
-

 config BUSYBOX_CONFIG_ASH_MAIL
 config BUSYBOX_CONFIG_ASH_MAIL

-       bool "  Check for new mail on interactive shells"
+       bool "Check for new mail on interactive shells"

        default n
        depends on BUSYBOX_CONFIG_ASH
        help
          Enable "check for new mail" in the ash shell.
 
 config BUSYBOX_CONFIG_ASH_OPTIMIZE_FOR_SIZE
        default n
        depends on BUSYBOX_CONFIG_ASH
        help
          Enable "check for new mail" in the ash shell.
 
 config BUSYBOX_CONFIG_ASH_OPTIMIZE_FOR_SIZE

-       bool "  Optimize for size instead of speed"
-       default y
+       bool "Optimize for size instead of speed"
+       default n

        depends on BUSYBOX_CONFIG_ASH
        help
          Compile ash for reduced size at the price of speed.
 
 config BUSYBOX_CONFIG_ASH_RANDOM_SUPPORT
        depends on BUSYBOX_CONFIG_ASH
        help
          Compile ash for reduced size at the price of speed.
 
 config BUSYBOX_CONFIG_ASH_RANDOM_SUPPORT

-       bool "  Enable pseudorandom generator and variable $RANDOM"
+       bool "Pseudorandom generator and $RANDOM variable"

        default n
        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.
        default n
        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" then generator will switch off and this
+         After "unset RANDOM" the generator will switch off and this

          variable will no longer have special treatment.
 
 config BUSYBOX_CONFIG_ASH_EXPAND_PRMT
          variable will no longer have special treatment.
 
 config BUSYBOX_CONFIG_ASH_EXPAND_PRMT

-       bool "  Expand prompt string"
-       default n
+       bool "Expand prompt string"
+       default y

        depends on BUSYBOX_CONFIG_ASH
        help
        depends on BUSYBOX_CONFIG_ASH
        help

-         "PS#" may be contain volatile content, such as backquote commands.
+         "PS#" may contain volatile content, such as backquote commands.

          This option recreates the prompt string from the environment
          variable each time it is displayed.
 
          This option recreates the prompt string from the environment
          variable each time it is displayed.
 

+config BUSYBOX_CONFIG_CTTYHACK
+       bool "cttyhack"
+       default n
+       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
+
+         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'
+

 config BUSYBOX_CONFIG_HUSH
        bool "hush"
        default n
 config BUSYBOX_CONFIG_HUSH
        bool "hush"
        default n

-       select BUSYBOX_CONFIG_TRUE
-       select BUSYBOX_CONFIG_FALSE
-       select BUSYBOX_CONFIG_TEST

        help
        help

-         hush is a very small shell (just 18k) and it has fairly complete
-         Bourne shell grammar.  It even handles all the normal flow control
-         options such as if/then/elif/else/fi, for/in/do/done, while loops,
-         etc.
+         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 does not handle case/esac, select, function, here documents ( <<
-         word ), arithmetic expansion, aliases, brace expansion, tilde
-         expansion, &> and >& redirection of stdout+stderr, etc.
+         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_LASH
-       bool "lash"
+config BUSYBOX_CONFIG_HUSH_BASH_COMPAT
+       bool "bash-compatible extensions"
+       default y
+       depends on BUSYBOX_CONFIG_HUSH
+       help
+         Enable bash-compatible extensions.
+
+config BUSYBOX_CONFIG_HUSH_BRACE_EXPANSION
+       bool "Brace expansion"

        default n
        default n

-       select BUSYBOX_CONFIG_TRUE
-       select BUSYBOX_CONFIG_FALSE
-       select BUSYBOX_CONFIG_TEST
+       depends on BUSYBOX_CONFIG_HUSH_BASH_COMPAT

        help
        help

-         lash is the very smallest shell (adds just 10k) and it is quite
-         usable as a command prompt, but it is not suitable for any but the
-         most trivial scripting (such as an initrd that calls insmod a few
-         times) since it does not understand any Bourne shell grammar.  It
-         does handle pipes, redirects, and job control though.  Adding in
-         command editing makes it a very nice lightweight command prompt.
+         Enable {abc,def} extension.

 
 

+config BUSYBOX_CONFIG_HUSH_HELP
+       bool "help builtin"
+       default y
+       depends on BUSYBOX_CONFIG_HUSH
+       help
+         Enable help builtin in hush. Code size + ~1 kbyte.

 
 

-config BUSYBOX_CONFIG_MSH
-       bool "msh"
+config BUSYBOX_CONFIG_HUSH_INTERACTIVE
+       bool "Interactive mode"
+       default y
+       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 n
        default n

-       select BUSYBOX_CONFIG_TRUE
-       select BUSYBOX_CONFIG_FALSE
-       select BUSYBOX_CONFIG_TEST
+       depends on BUSYBOX_CONFIG_HUSH_INTERACTIVE && BUSYBOX_CONFIG_FEATURE_EDITING_SAVEHISTORY

        help
        help

-         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 also uses only vfork, so it can be used on uClinux systems.
+         Enable history saving in hush.

 
 

-comment "Bourne Shell Options"
-       depends on BUSYBOX_CONFIG_MSH || BUSYBOX_CONFIG_LASH || BUSYBOX_CONFIG_HUSH || BUSYBOX_CONFIG_ASH
+config BUSYBOX_CONFIG_HUSH_JOB
+       bool "Job control"
+       default y
+       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 y
+       depends on BUSYBOX_CONFIG_HUSH
+       help
+         Enable process substitution `command` and $(command) in hush.

 
 

-config BUSYBOX_CONFIG_FEATURE_SH_EXTRA_QUIET
-       bool "Hide message on interactive shell startup"
-       default n
-       depends on BUSYBOX_CONFIG_MSH || BUSYBOX_CONFIG_LASH || BUSYBOX_CONFIG_HUSH || BUSYBOX_CONFIG_ASH
+config BUSYBOX_CONFIG_HUSH_IF
+       bool "Support if/then/elif/else/fi"
+       default y
+       depends on BUSYBOX_CONFIG_HUSH

        help
        help

-         Remove the busybox introduction when starting a shell.
+         Enable if/then/elif/else/fi in hush.

 
 

-config BUSYBOX_CONFIG_FEATURE_SH_STANDALONE_SHELL
-       bool "Standalone shell"
-       default n
-       depends on BUSYBOX_CONFIG_MSH || BUSYBOX_CONFIG_LASH || BUSYBOX_CONFIG_HUSH || BUSYBOX_CONFIG_ASH
+config BUSYBOX_CONFIG_HUSH_LOOPS
+       bool "Support for, while and until loops"
+       default y
+       depends on BUSYBOX_CONFIG_HUSH

        help
        help

-         This option causes the selected busybox shell 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.
+         Enable for, while and until loops in hush.

 
 

-         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_HUSH_CASE
+       bool "Support case ... esac statement"
+       default y
+       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 y
+       depends on BUSYBOX_CONFIG_HUSH
+       help
+         Enable support for shell functions in hush. +800 bytes.

 
 

-config BUSYBOX_CONFIG_FEATURE_COMMAND_EDITING
-       bool "command line editing"
+config BUSYBOX_CONFIG_HUSH_LOCAL
+       bool "Support local builtin"

        default y
        default y

-       depends on BUSYBOX_CONFIG_MSH || BUSYBOX_CONFIG_LASH || BUSYBOX_CONFIG_HUSH || BUSYBOX_CONFIG_ASH
+       depends on BUSYBOX_CONFIG_HUSH_FUNCTIONS

        help
        help

-         Enable command editing in shell.
+         Enable support for local variables in functions.

 
 

-config BUSYBOX_CONFIG_FEATURE_COMMAND_EDITING_VI
-       bool "vi-style line editing commands"
+config BUSYBOX_CONFIG_HUSH_RANDOM_SUPPORT
+       bool "Pseudorandom generator and $RANDOM variable"

        default n
        default n

-       depends on BUSYBOX_CONFIG_FEATURE_COMMAND_EDITING
+       depends on BUSYBOX_CONFIG_HUSH

        help
        help

-         Enable vi-style line editing in the shell.  This mode can be
-         turned on and off with "set -o vi" and "set +o vi".
+         Enable pseudorandom generator and dynamic variable "$RANDOM".
+         Each read of "$RANDOM" will generate a new pseudorandom value.

 
 

-config BUSYBOX_CONFIG_FEATURE_COMMAND_HISTORY
-       int "history size"
-       default 15
-       depends on BUSYBOX_CONFIG_FEATURE_COMMAND_EDITING
+config BUSYBOX_CONFIG_HUSH_EXPORT_N
+       bool "Support 'export -n' option"
+       default y
+       depends on BUSYBOX_CONFIG_HUSH

        help
        help

-         Specify command history size in shell.
+         export -n unexports variables. It is a bash extension.

 
 

-config BUSYBOX_CONFIG_FEATURE_COMMAND_SAVEHISTORY
-       bool "history saving"
+config BUSYBOX_CONFIG_HUSH_MODE_X
+       bool "Support 'hush -x' option and 'set -x' command"

        default n
        default n

-       depends on BUSYBOX_CONFIG_ASH && BUSYBOX_CONFIG_FEATURE_COMMAND_EDITING
+       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 n
+       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
        help

-         Enable history saving in ash shell.
+         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_COMMAND_TAB_COMPLETION
-       bool "tab completion"
+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 y
        default y

-       depends on BUSYBOX_CONFIG_FEATURE_COMMAND_EDITING
+       depends on BUSYBOX_CONFIG_ASH || BUSYBOX_CONFIG_HUSH

        help
        help

-         Enable tab completion in shell.
+         Enable math support in the shell via $((...)) syntax.

 
 

-config BUSYBOX_CONFIG_FEATURE_COMMAND_USERNAME_COMPLETION
-       bool "username completion"
+config BUSYBOX_CONFIG_SH_MATH_SUPPORT_64
+       bool "Extend POSIX math support to 64 bit"
+       default y
+       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 n
        default n

-       depends on BUSYBOX_CONFIG_FEATURE_COMMAND_TAB_COMPLETION
+       depends on BUSYBOX_CONFIG_HUSH || BUSYBOX_CONFIG_ASH

        help
        help

-         Enable username completion in shell.
+         Remove the busybox introduction when starting a shell.

 
 

-config BUSYBOX_CONFIG_FEATURE_SH_FANCY_PROMPT
-       bool "Fancy shell prompts"
-       default y
-       depends on BUSYBOX_CONFIG_FEATURE_COMMAND_EDITING
+config BUSYBOX_CONFIG_FEATURE_SH_STANDALONE
+       bool "Standalone shell"
+       default n
+       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 n
+       depends on (BUSYBOX_CONFIG_HUSH || BUSYBOX_CONFIG_ASH) && BUSYBOX_CONFIG_FEATURE_PREFER_APPLETS

        help
        help

-         Setting this option allows for prompts to use things like \w and
-         \$ and also using escape codes.
+         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
 
 endmenu