| # |
| # For a description of the syntax of this configuration file, |
| # see scripts/kbuild/config-language.txt. |
| # |
| |
| menu "Shells" |
| |
| choice |
| prompt "Choose your default shell" |
| default FEATURE_SH_IS_NONE |
| help |
| Choose a shell. The ash shell is the most bash compatible |
| and full featured one. |
| |
| config FEATURE_SH_IS_ASH |
| select ASH |
| bool "ash" |
| |
| config FEATURE_SH_IS_HUSH |
| select HUSH |
| bool "hush" |
| |
| ####config FEATURE_SH_IS_LASH |
| #### select LASH |
| #### bool "lash" |
| |
| config FEATURE_SH_IS_MSH |
| select MSH |
| bool "msh" |
| |
| config FEATURE_SH_IS_NONE |
| bool "none" |
| |
| endchoice |
| |
| config ASH |
| bool "ash" |
| default n |
| 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. |
| |
| comment "Ash Shell Options" |
| depends on ASH |
| |
| config ASH_BASH_COMPAT |
| bool "bash-compatible extensions" |
| default y |
| depends on ASH |
| help |
| Enable bash-conpatible extensions. |
| |
| config ASH_JOB_CONTROL |
| bool "Job control" |
| default y |
| depends on ASH |
| help |
| Enable job control in the ash shell. |
| |
| config ASH_READ_NCHARS |
| bool "'read -n N' and 'read -s' support" |
| default n |
| depends on 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. |
| |
| config ASH_READ_TIMEOUT |
| bool "'read -t S' support." |
| default n |
| depends on 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'. |
| |
| config ASH_ALIAS |
| bool "alias support" |
| default y |
| depends on ASH |
| help |
| Enable alias support in the ash shell. |
| |
| config ASH_MATH_SUPPORT |
| bool "Posix math support" |
| default y |
| depends on ASH |
| help |
| Enable math support in the ash shell. |
| |
| config ASH_MATH_SUPPORT_64 |
| bool "Extend Posix math support to 64 bit" |
| default n |
| depends on 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 ASH_GETOPTS |
| bool "Builtin getopt to parse positional parameters" |
| default n |
| 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_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 n |
| 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 y |
| 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 variable $RANDOM" |
| default n |
| depends on ASH |
| help |
| Enable pseudorandom generator and dynamic variable "$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" then generator will switch off and this |
| variable will no longer have special treatment. |
| |
| config ASH_EXPAND_PRMT |
| bool "Expand prompt string" |
| default n |
| depends on ASH |
| help |
| "PS#" may be contain volatile content, such as backquote commands. |
| This option recreates the prompt string from the environment |
| variable each time it is displayed. |
| |
| config HUSH |
| bool "hush" |
| default n |
| 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. |
| |
| It does not handle case/esac, select, function, here documents ( << |
| word ), arithmetic expansion, aliases, brace expansion, tilde |
| expansion, &> and >& redirection of stdout+stderr, etc. |
| |
| config HUSH_HELP |
| bool "help builtin" |
| default n |
| depends on HUSH |
| help |
| Enable help builtin in hush. Code size + ~1 kbyte. |
| |
| config HUSH_INTERACTIVE |
| bool "Interactive mode" |
| default y |
| depends on 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 the file. |
| No prompt, no PS1/PS2 magic shell variables. |
| |
| config HUSH_JOB |
| bool "Job control" |
| default n |
| depends on 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 HUSH_TICK |
| bool "Process substitution" |
| default n |
| depends on HUSH |
| help |
| Enable process substitution `command` and $(command) in hush. |
| |
| config HUSH_IF |
| bool "Support if/then/elif/else/fi" |
| default n |
| depends on HUSH |
| help |
| Enable if/then/elif/else/fi in hush. |
| |
| config HUSH_LOOPS |
| bool "Support for, while and until loops" |
| default n |
| depends on HUSH |
| help |
| Enable for, while and until loops in hush. |
| |
| config LASH |
| bool "lash" |
| default n |
| select HUSH |
| help |
| lash is deprecated and will be removed, please migrate to hush. |
| |
| config MSH |
| bool "msh" |
| default n |
| 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. |
| |
| comment "Bourne Shell Options" |
| depends on MSH || LASH || HUSH || ASH |
| |
| config FEATURE_SH_EXTRA_QUIET |
| bool "Hide message on interactive shell startup" |
| default n |
| depends on MSH || LASH || HUSH || ASH |
| help |
| Remove the busybox introduction when starting a shell. |
| |
| config FEATURE_SH_STANDALONE |
| bool "Standalone shell" |
| default n |
| depends on (MSH || LASH || 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 (MSH || LASH || 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. |
| |
| 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. Usage example for /etc/inittab |
| (for busybox init): |
| |
| ::respawn:/bin/cttyhack /bin/sh |
| |
| endmenu |