2 # For a description of the syntax of this configuration file,
3 # see scripts/kbuild/config-language.txt.
6 mainmenu "BusyBox Configuration"
12 menu "Busybox Settings"
14 menu "General Configuration"
17 bool "Enable options for full-blown desktop systems"
20 Enable options and features which are not essential.
21 Select this only if you plan to use busybox on full-blown
22 desktop machine with common Linux distro, not on an embedded box.
25 bool "Provide compatible behavior for rare corner cases (bigger code)"
28 This option makes grep, sed etc handle rare corner cases
29 (embedded NUL bytes and such). This makes code bigger and uses
30 some GNU extensions in libc. You probably only need this option
31 if you plan to run busybox on desktop.
34 bool "Enable obsolete features removed before SUSv3"
37 This option will enable backwards compatibility with SuSv2,
38 specifically, old-style numeric options ('command -1 <file>')
39 will be supported in head, tail, and fold. (Note: should
42 config USE_PORTABLE_CODE
43 bool "Avoid using GCC-specific code constructs"
46 Use this option if you are trying to compile busybox with
47 compiler other than gcc.
48 If you do use gcc, this option may needlessly increase code size.
51 bool "Enable Linux-specific applets and features"
54 For the most part, busybox requires only POSIX compatibility
55 from the target system, but some applets and features use
56 Linux-specific interfaces.
58 Answering 'N' here will disable such applets and hide the
59 corresponding configuration options.
62 prompt "Buffer allocation policy"
63 default FEATURE_BUFFERS_USE_MALLOC
65 There are 3 ways BusyBox can handle buffer allocations:
66 - Use malloc. This costs code size for the call to xmalloc.
67 - Put them on stack. For some very small machines with limited stack
68 space, this can be deadly. For most folks, this works just fine.
69 - Put them in BSS. This works beautifully for computers with a real
70 MMU (and OS support), but wastes runtime RAM for uCLinux. This
71 behavior was the only one available for BusyBox versions 0.48 and
74 config FEATURE_BUFFERS_USE_MALLOC
75 bool "Allocate with Malloc"
77 config FEATURE_BUFFERS_GO_ON_STACK
78 bool "Allocate on the Stack"
80 config FEATURE_BUFFERS_GO_IN_BSS
81 bool "Allocate in the .bss section"
86 bool "Show applet usage messages"
89 Enabling this option, BusyBox applets will show terse help messages
90 when invoked with wrong arguments.
91 If you do not want to show any (helpful) usage message when
92 issuing wrong command syntax, you can say 'N' here,
93 saving approximately 7k.
95 config FEATURE_VERBOSE_USAGE
96 bool "Show verbose applet usage messages"
100 All BusyBox applets will show verbose help messages when
101 busybox is invoked with --help. This will add a lot of text to the
102 busybox binary. In the default configuration, this will add about
103 13k, but it can add much more depending on your configuration.
105 config FEATURE_COMPRESS_USAGE
106 bool "Store applet usage messages in compressed form"
108 depends on SHOW_USAGE
110 Store usage messages in .bz compressed form, uncompress them
111 on-the-fly when <applet> --help is called.
113 If you have a really tiny busybox with few applets enabled (and
114 bunzip2 isn't one of them), the overhead of the decompressor might
115 be noticeable. Also, if you run executables directly from ROM
116 and have very little memory, this might not be a win. Otherwise,
117 you probably want this.
119 config FEATURE_INSTALLER
120 bool "Support --install [-s] to install applet links at runtime"
123 Enable 'busybox --install [-s]' support. This will allow you to use
124 busybox at runtime to create hard links or symlinks for all the
125 applets that are compiled into busybox.
127 config INSTALL_NO_USR
128 bool "Don't use /usr"
131 Disable use of /usr. busybox --install and "make install"
132 will install applets only to /bin and /sbin,
133 never to /usr/bin or /usr/sbin.
135 config LOCALE_SUPPORT
136 bool "Enable locale support (system needs locale for this to work)"
139 Enable this if your system has locale support and you would like
140 busybox to support locale settings.
142 config UNICODE_SUPPORT
143 bool "Support Unicode"
146 This makes various applets aware that one byte is not
147 one character on screen.
149 Busybox aims to eventually work correctly with Unicode displays.
150 Any older encodings are not guaranteed to work.
151 Probably by the time when busybox will be fully Unicode-clean,
152 other encodings will be mainly of historic interest.
154 config UNICODE_USING_LOCALE
155 bool "Use libc routines for Unicode (else uses internal ones)"
157 depends on UNICODE_SUPPORT && LOCALE_SUPPORT
159 With this option on, Unicode support is implemented using libc
160 routines. Otherwise, internal implementation is used.
161 Internal implementation is smaller.
163 config FEATURE_CHECK_UNICODE_IN_ENV
164 bool "Check $LC_ALL, $LC_CTYPE and $LANG environment variables"
166 depends on UNICODE_SUPPORT && !UNICODE_USING_LOCALE
168 With this option on, Unicode support is activated
169 only if locale-related variables have the value of the form
172 Otherwise, Unicode support will be always enabled and active.
175 int "Character code to substitute unprintable characters with"
176 depends on UNICODE_SUPPORT
179 Typical values are 63 for '?' (works with any output device),
180 30 for ASCII substitute control code,
181 65533 (0xfffd) for Unicode replacement character.
183 config LAST_SUPPORTED_WCHAR
184 int "Range of supported Unicode characters"
185 depends on UNICODE_SUPPORT
188 Any character with Unicode value bigger than this is assumed
189 to be non-printable on output device. Many applets replace
190 such chars with substitution character.
192 The idea is that many valid printable Unicode chars are
193 nevertheless are not displayed correctly. Think about
194 combining charachers, double-wide hieroglyphs, obscure
195 characters in dozens of ancient scripts...
196 Many terminals, terminal emulators, xterms etc will fail
197 to handle them correctly. Choose the smallest value
198 which suits your needs.
202 767 (0x2ff) - there are no combining chars in [0..767] range
203 (the range includes Latin 1, Latin Ext. A and B),
204 code is ~700 bytes smaller for this case.
205 4351 (0x10ff) - there are no double-wide chars in [0..4351] range,
206 code is ~300 bytes smaller for this case.
207 12799 (0x31ff) - nearly all non-ideographic characters are
208 available in [0..12799] range, including
209 East Asian scripts like katakana, hiragana, hangul,
211 0 - off, any valid printable Unicode character will be printed.
213 config UNICODE_COMBINING_WCHARS
214 bool "Allow zero-width Unicode characters on output"
216 depends on UNICODE_SUPPORT
218 With this option off, any Unicode char with width of 0
219 is substituted on output.
221 config UNICODE_WIDE_WCHARS
222 bool "Allow wide Unicode characters on output"
224 depends on UNICODE_SUPPORT
226 With this option off, any Unicode char with width > 1
227 is substituted on output.
229 config UNICODE_BIDI_SUPPORT
230 bool "Bidirectional character-aware line input"
232 depends on UNICODE_SUPPORT && !UNICODE_USING_LOCALE
234 With this option on, right-to-left Unicode characters
235 are treated differently on input (e.g. cursor movement).
237 config UNICODE_NEUTRAL_TABLE
238 bool "In bidi input, support non-ASCII neutral chars too"
240 depends on UNICODE_BIDI_SUPPORT
242 In most cases it's enough to treat only ASCII non-letters
243 (i.e. punctuation, numbers and space) as characters
244 with neutral directionality.
245 With this option on, more extensive (and bigger) table
246 of neutral chars will be used.
248 config UNICODE_PRESERVE_BROKEN
249 bool "Make it possible to enter sequences of chars which are not Unicode"
251 depends on UNICODE_SUPPORT
253 With this option on, on line-editing input (such as used by shells)
254 invalid UTF-8 bytes are not substituted with the selected
255 substitution character.
256 For example, this means that entering 'l', 's', ' ', 0xff, [Enter]
257 at shell prompt will list file named 0xff (single char name
258 with char value 255), not file named '?'.
261 bool "Support for PAM (Pluggable Authentication Modules)"
264 Use PAM in some busybox applets (currently login and httpd) instead
265 of direct access to password database.
267 config FEATURE_USE_SENDFILE
268 bool "Use sendfile system call"
271 When enabled, busybox will use the kernel sendfile() function
272 instead of read/write loops to copy data between file descriptors
273 (for example, cp command does this a lot).
274 If sendfile() doesn't work, copying code falls back to read/write
275 loop. sendfile() was originally implemented for faster I/O
276 from files to sockets, but since Linux 2.6.33 it was extended
277 to work for many more file types.
280 bool "Support for --long-options"
283 Enable this if you want busybox applets to use the gnu --long-option
284 style, in addition to single character -a -b -c style options.
286 config FEATURE_DEVPTS
287 bool "Use the devpts filesystem for Unix98 PTYs"
290 Enable if you want BusyBox to use Unix98 PTY support. If enabled,
291 busybox will use /dev/ptmx for the master side of the pseudoterminal
292 and /dev/pts/<number> for the slave side. Otherwise, BSD style
293 /dev/ttyp<number> will be used. To use this option, you should have
296 config FEATURE_CLEAN_UP
297 bool "Clean up all memory before exiting (usually not needed)"
300 As a size optimization, busybox normally exits without explicitly
301 freeing dynamically allocated memory or closing files. This saves
302 space since the OS will clean up for us, but it can confuse debuggers
303 like valgrind, which report tons of memory and resource leaks.
305 Don't enable this unless you have a really good reason to clean
309 bool "Support utmp file"
312 The file /var/run/utmp is used to track who is currently logged in.
313 With this option on, certain applets (getty, login, telnetd etc)
314 will create and delete entries there.
315 "who" applet requires this option.
318 bool "Support wtmp file"
320 depends on FEATURE_UTMP
322 The file /var/run/wtmp is used to track when users have logged into
323 and logged out of the system.
324 With this option on, certain applets (getty, login, telnetd etc)
325 will append new entries there.
326 "last" applet requires this option.
328 config FEATURE_PIDFILE
329 bool "Support writing pidfiles"
332 This option makes some applets (e.g. crond, syslogd, inetd) write
333 a pidfile at the configured PID_FILE_PATH. It has no effect
334 on applets which require pidfiles to run.
337 string "Path to directory for pidfile"
339 depends on FEATURE_PIDFILE
341 This is the default path where pidfiles are created. Applets which
342 allow you to set the pidfile path on the command line will override
343 this value. The option has no effect on applets that require you to
344 specify a pidfile path.
347 bool "Support for SUID/SGID handling"
350 With this option you can install the busybox binary belonging
351 to root with the suid bit set, enabling some applets to perform
352 root-level operations even when run by ordinary users
353 (for example, mounting of user mounts in fstab needs this).
355 Busybox will automatically drop privileges for applets
356 that don't need root access.
358 If you are really paranoid and don't want to do this, build two
359 busybox binaries with different applets in them (and the appropriate
360 symlinks pointing to each binary), and only set the suid bit on the
363 The applets which require root rights (need suid bit or
364 to be run by root) and will refuse to execute otherwise:
365 crontab, login, passwd, su, vlock, wall.
367 The applets which will use root rights if they have them
368 (via suid bit, or because run by root), but would try to work
369 without root right nevertheless:
370 findfs, ping[6], traceroute[6], mount.
372 Note that if you DONT select this option, but DO make busybox
373 suid root, ALL applets will run under root, which is a huge
374 security hole (think "cp /some/file /etc/passwd").
376 config FEATURE_SUID_CONFIG
377 bool "Runtime SUID/SGID configuration via /etc/busybox.conf"
379 depends on FEATURE_SUID
381 Allow the SUID / SGID state of an applet to be determined at runtime
382 by checking /etc/busybox.conf. (This is sort of a poor man's sudo.)
383 The format of this file is as follows:
385 APPLET = [Ssx-][Ssx-][x-] [USER.GROUP]
387 s: USER or GROUP is allowed to execute APPLET.
388 APPLET will run under USER or GROUP
389 (reagardless of who's running it).
390 S: USER or GROUP is NOT allowed to execute APPLET.
391 APPLET will run under USER or GROUP.
392 This option is not very sensical.
393 x: USER/GROUP/others are allowed to execute APPLET.
394 No UID/GID change will be done when it is run.
395 -: USER/GROUP/others are not allowed to execute APPLET.
397 An example might help:
400 su = ssx root.0 # applet su can be run by anyone and runs with
402 su = ssx # exactly the same
404 mount = sx- root.disk # applet mount can be run by root and members
405 # of group disk (but not anyone else)
406 # and runs with euid=0 (egid is not changed)
408 cp = --- # disable applet cp for everyone
410 The file has to be owned by user root, group root and has to be
411 writeable only by root:
412 (chown 0.0 /etc/busybox.conf; chmod 600 /etc/busybox.conf)
413 The busybox executable has to be owned by user root, group
414 root and has to be setuid root for this to work:
415 (chown 0.0 /bin/busybox; chmod 4755 /bin/busybox)
417 Robert 'sandman' Griebl has more information here:
418 <url: http://www.softforge.de/bb/suid.html >.
420 config FEATURE_SUID_CONFIG_QUIET
421 bool "Suppress warning message if /etc/busybox.conf is not readable"
423 depends on FEATURE_SUID_CONFIG
425 /etc/busybox.conf should be readable by the user needing the SUID,
426 check this option to avoid users to be notified about missing
430 bool "Support NSA Security Enhanced Linux"
432 select PLATFORM_LINUX
434 Enable support for SELinux in applets ls, ps, and id. Also provide
435 the option of compiling in SELinux applets.
437 If you do not have a complete SELinux userland installed, this stuff
438 will not compile. Specifially, libselinux 1.28 or better is
439 directly required by busybox. If the installation is located in a
440 non-standard directory, provide it by invoking make as follows:
441 CFLAGS=-I<libselinux-include-path> \
442 LDFLAGS=-L<libselinux-lib-path> \
445 Most people will leave this set to 'N'.
447 config FEATURE_PREFER_APPLETS
448 bool "exec prefers applets"
451 This is an experimental option which directs applets about to
452 call 'exec' to try and find an applicable busybox applet before
453 searching the PATH. This is typically done by exec'ing
455 This may affect shell, find -exec, xargs and similar applets.
456 They will use applets even if /bin/<applet> -> busybox link
457 is missing (or is not a link to busybox). However, this causes
458 problems in chroot jails without mounted /proc and with ps/top
459 (command name can be shown as 'exe' for applets started this way).
461 config BUSYBOX_EXEC_PATH
462 string "Path to BusyBox executable"
463 default "/proc/self/exe"
465 When Busybox applets need to run other busybox applets, BusyBox
466 sometimes needs to exec() itself. When the /proc filesystem is
467 mounted, /proc/self/exe always points to the currently running
468 executable. If you haven't got /proc, set this to wherever you
469 want to run BusyBox from.
471 # These are auto-selected by other options
473 config FEATURE_SYSLOG
474 bool #No description makes it a hidden option
477 # This option is auto-selected when you select any applet which may
478 # send its output to syslog. You do not need to select it manually.
480 config FEATURE_HAVE_RPC
481 bool #No description makes it a hidden option
484 # This is automatically selected if any of enabled applets need it.
485 # You do not need to select it manually.
492 bool "Build BusyBox as a static binary (no shared libs)"
495 If you want to build a static BusyBox binary, which does not
496 use or require any shared libraries, then enable this option.
497 This can cause BusyBox to be considerably larger, so you should
498 leave this option false unless you have a good reason (i.e.
499 your target platform does not support shared libraries, or
500 you are building an initrd which doesn't need anything but
503 Most people will leave this set to 'N'.
506 bool "Build BusyBox as a position independent executable"
510 Hardened code option. PIE binaries are loaded at a different
511 address at each invocation. This has some overhead,
512 particularly on x86-32 which is short on registers.
514 Most people will leave this set to 'N'.
517 bool "Force NOMMU build"
520 Busybox tries to detect whether architecture it is being
521 built against supports MMU or not. If this detection fails,
522 or if you want to build NOMMU version of busybox for testing,
523 you may force NOMMU build here.
525 Most people will leave this set to 'N'.
527 # PIE can be made to work with BUILD_LIBBUSYBOX, but currently
528 # build system does not support that
529 config BUILD_LIBBUSYBOX
530 bool "Build shared libbusybox"
532 depends on !FEATURE_PREFER_APPLETS && !PIE && !STATIC
534 Build a shared library libbusybox.so.N.N.N which contains all
537 This feature allows every applet to be built as a tiny
538 separate executable. Enabling it for "one big busybox binary"
539 approach serves no purpose and increases code size.
540 You should almost certainly say "no" to this.
542 ### config FEATURE_FULL_LIBBUSYBOX
543 ### bool "Feature-complete libbusybox"
544 ### default n if !FEATURE_SHARED_BUSYBOX
545 ### depends on BUILD_LIBBUSYBOX
547 ### Build a libbusybox with the complete feature-set, disregarding
548 ### the actually selected config.
550 ### Normally, libbusybox will only contain the features which are
551 ### used by busybox itself. If you plan to write a separate
552 ### standalone application which uses libbusybox say 'Y'.
554 ### Note: libbusybox is GPL, not LGPL, and exports no stable API that
555 ### might act as a copyright barrier. We can and will modify the
556 ### exported function set between releases (even minor version number
557 ### changes), and happily break out-of-tree features.
559 ### Say 'N' if in doubt.
561 config FEATURE_INDIVIDUAL
562 bool "Produce a binary for each applet, linked against libbusybox"
564 depends on BUILD_LIBBUSYBOX
566 If your CPU architecture doesn't allow for sharing text/rodata
567 sections of running binaries, but allows for runtime dynamic
568 libraries, this option will allow you to reduce memory footprint
569 when you have many different applets running at once.
571 If your CPU architecture allows for sharing text/rodata,
572 having single binary is more optimal.
574 Each applet will be a tiny program, dynamically linked
575 against libbusybox.so.N.N.N.
577 You need to have a working dynamic linker.
579 config FEATURE_SHARED_BUSYBOX
580 bool "Produce additional busybox binary linked against libbusybox"
582 depends on BUILD_LIBBUSYBOX
584 Build busybox, dynamically linked against libbusybox.so.N.N.N.
586 You need to have a working dynamic linker.
588 ### config BUILD_AT_ONCE
589 ### bool "Compile all sources at once"
592 ### Normally each source-file is compiled with one invocation of
594 ### If you set this option, all sources are compiled at once.
595 ### This gives the compiler more opportunities to optimize which can
596 ### result in smaller and/or faster binaries.
598 ### Setting this option will consume alot of memory, e.g. if you
599 ### enable all applets with all features, gcc uses more than 300MB
600 ### RAM during compilation of busybox.
602 ### This option is most likely only beneficial for newer compilers
603 ### such as gcc-4.1 and above.
605 ### Say 'N' unless you know what you are doing.
608 bool "Build with Large File Support (for accessing files > 2 GB)"
611 If you want to build BusyBox with large file support, then enable
612 this option. This will have no effect if your kernel or your C
613 library lacks large file support for large files. Some of the
614 programs that can benefit from large file support include dd, gzip,
615 cp, mount, tar, and many others. If you want to access files larger
616 than 2 Gigabytes, enable this option. Otherwise, leave it set to 'N'.
618 config CROSS_COMPILER_PREFIX
619 string "Cross Compiler prefix"
622 If you want to build BusyBox with a cross compiler, then you
623 will need to set this to the cross-compiler prefix, for example,
626 Note that CROSS_COMPILE environment variable or
627 "make CROSS_COMPILE=xxx ..." will override this selection.
629 Native builds leave this empty.
632 string "Path to sysroot"
635 If you want to build BusyBox with a cross compiler, then you
636 might also need to specify where /usr/include and /usr/lib
639 For example, BusyBox can be built against an installed
640 Android NDK, platform version 9, for ARM ABI with
642 CONFIG_SYSROOT=/opt/android-ndk/platforms/android-9/arch-arm
644 Native builds leave this empty.
647 string "Additional CFLAGS"
650 Additional CFLAGS to pass to the compiler verbatim.
653 string "Additional LDFLAGS"
656 Additional LDFLAGS to pass to the linker verbatim.
659 string "Additional LDLIBS"
662 Additional LDLIBS to pass to the linker with -l.
666 menu 'Debugging Options'
669 bool "Build BusyBox with extra Debugging symbols"
672 Say Y here if you wish to examine BusyBox internals while applets are
673 running. This increases the size of the binary considerably, and
674 should only be used when doing development. If you are doing
675 development and want to debug BusyBox, answer Y.
677 Most people should answer N.
679 config DEBUG_PESSIMIZE
680 bool "Disable compiler optimizations"
684 The compiler's optimization of source code can eliminate and reorder
685 code, resulting in an executable that's hard to understand when
686 stepping through it with a debugger. This switches it off, resulting
687 in a much bigger executable that more closely matches the source
691 bool "Build unit tests"
694 Say Y here if you want to build unit tests (both the framework and
695 test cases) as a Busybox applet. This results in bigger code, so you
696 probably don't want this option in production builds.
699 bool "Abort compilation on any warning"
702 Selecting this will add -Werror to gcc command line.
704 Most people should answer N.
707 prompt "Additional debugging library"
710 Using an additional debugging library will make BusyBox become
711 considerable larger and will cause it to run more slowly. You
712 should always leave this option disabled for production use.
716 This enables compiling with dmalloc ( http://dmalloc.com/ )
717 which is an excellent public domain mem leak and malloc problem
718 detector. To enable dmalloc, before running busybox you will
719 want to properly set your environment, for example:
720 export DMALLOC_OPTIONS=debug=0x34f47d83,inter=100,log=logfile
721 The 'debug=' value is generated using the following command
722 dmalloc -p log-stats -p log-non-free -p log-bad-space \
723 -p log-elapsed-time -p check-fence -p check-heap \
724 -p check-lists -p check-blank -p check-funcs -p realloc-copy \
727 Electric-fence support:
728 -----------------------
729 This enables compiling with Electric-fence support. Electric
730 fence is another very useful malloc debugging library which uses
731 your computer's virtual memory hardware to detect illegal memory
732 accesses. This support will make BusyBox be considerable larger
733 and run slower, so you should leave this option disabled unless
734 you are hunting a hard to find memory problem.
744 bool "Electric-fence"
750 menu 'Installation Options ("make install" behavior)'
753 prompt "What kind of applet links to install"
754 default INSTALL_APPLET_SYMLINKS
756 Choose what kind of links to applets are created by "make install".
758 config INSTALL_APPLET_SYMLINKS
761 Install applets as soft-links to the busybox binary. This needs some
762 free inodes on the filesystem, but might help with filesystem
763 generators that can't cope with hard-links.
765 config INSTALL_APPLET_HARDLINKS
768 Install applets as hard-links to the busybox binary. This might
769 count on a filesystem with few inodes.
771 config INSTALL_APPLET_SCRIPT_WRAPPERS
772 bool "as script wrappers"
774 Install applets as script wrappers that call the busybox binary.
776 config INSTALL_APPLET_DONT
779 Do not install applet links. Useful when you plan to use
780 busybox --install for installing links, or plan to use
781 a standalone shell and thus don't need applet links.
786 prompt "/bin/sh applet link"
787 default INSTALL_SH_APPLET_SYMLINK
788 depends on INSTALL_APPLET_SCRIPT_WRAPPERS
790 Choose how you install /bin/sh applet link.
792 config INSTALL_SH_APPLET_SYMLINK
795 Install /bin/sh applet as soft-link to the busybox binary.
797 config INSTALL_SH_APPLET_HARDLINK
800 Install /bin/sh applet as hard-link to the busybox binary.
802 config INSTALL_SH_APPLET_SCRIPT_WRAPPER
803 bool "as script wrapper"
805 Install /bin/sh applet as script wrapper that calls
811 string "BusyBox installation prefix"
814 Define your directory to install BusyBox files/subdirs in.
818 source libbb/Config.in
824 source archival/Config.in
825 source coreutils/Config.in
826 source console-tools/Config.in
827 source debianutils/Config.in
828 source editors/Config.in
829 source findutils/Config.in
830 source init/Config.in
831 source loginutils/Config.in
832 source e2fsprogs/Config.in
833 source modutils/Config.in
834 source util-linux/Config.in
835 source miscutils/Config.in
836 source networking/Config.in
837 source printutils/Config.in
838 source mailutils/Config.in
839 source procps/Config.in
840 source runit/Config.in
841 source selinux/Config.in
842 source shell/Config.in
843 source sysklogd/Config.in