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"
270 select PLATFORM_LINUX
272 When enabled, busybox will use the kernel sendfile() function
273 instead of read/write loops to copy data between file descriptors
274 (for example, cp command does this a lot).
275 If sendfile() doesn't work, copying code falls back to read/write
276 loop. sendfile() was originally implemented for faster I/O
277 from files to sockets, but since Linux 2.6.33 it was extended
278 to work for many more file types.
281 bool "Support for --long-options"
284 Enable this if you want busybox applets to use the gnu --long-option
285 style, in addition to single character -a -b -c style options.
287 config FEATURE_DEVPTS
288 bool "Use the devpts filesystem for Unix98 PTYs"
291 Enable if you want BusyBox to use Unix98 PTY support. If enabled,
292 busybox will use /dev/ptmx for the master side of the pseudoterminal
293 and /dev/pts/<number> for the slave side. Otherwise, BSD style
294 /dev/ttyp<number> will be used. To use this option, you should have
297 config FEATURE_CLEAN_UP
298 bool "Clean up all memory before exiting (usually not needed)"
301 As a size optimization, busybox normally exits without explicitly
302 freeing dynamically allocated memory or closing files. This saves
303 space since the OS will clean up for us, but it can confuse debuggers
304 like valgrind, which report tons of memory and resource leaks.
306 Don't enable this unless you have a really good reason to clean
310 bool "Support utmp file"
313 The file /var/run/utmp is used to track who is currently logged in.
314 With this option on, certain applets (getty, login, telnetd etc)
315 will create and delete entries there.
316 "who" applet requires this option.
319 bool "Support wtmp file"
321 depends on FEATURE_UTMP
323 The file /var/run/wtmp is used to track when users have logged into
324 and logged out of the system.
325 With this option on, certain applets (getty, login, telnetd etc)
326 will append new entries there.
327 "last" applet requires this option.
329 config FEATURE_PIDFILE
330 bool "Support writing pidfiles"
333 This option makes some applets (e.g. crond, syslogd, inetd) write
334 a pidfile at the configured PID_FILE_PATH. It has no effect
335 on applets which require pidfiles to run.
338 string "Path to directory for pidfile"
340 depends on FEATURE_PIDFILE
342 This is the default path where pidfiles are created. Applets which
343 allow you to set the pidfile path on the command line will override
344 this value. The option has no effect on applets that require you to
345 specify a pidfile path.
348 bool "Support for SUID/SGID handling"
351 With this option you can install the busybox binary belonging
352 to root with the suid bit set, enabling some applets to perform
353 root-level operations even when run by ordinary users
354 (for example, mounting of user mounts in fstab needs this).
356 Busybox will automatically drop privileges for applets
357 that don't need root access.
359 If you are really paranoid and don't want to do this, build two
360 busybox binaries with different applets in them (and the appropriate
361 symlinks pointing to each binary), and only set the suid bit on the
364 The applets which require root rights (need suid bit or
365 to be run by root) and will refuse to execute otherwise:
366 crontab, login, passwd, su, vlock, wall.
368 The applets which will use root rights if they have them
369 (via suid bit, or because run by root), but would try to work
370 without root right nevertheless:
371 findfs, ping[6], traceroute[6], mount.
373 Note that if you DONT select this option, but DO make busybox
374 suid root, ALL applets will run under root, which is a huge
375 security hole (think "cp /some/file /etc/passwd").
377 config FEATURE_SUID_CONFIG
378 bool "Runtime SUID/SGID configuration via /etc/busybox.conf"
380 depends on FEATURE_SUID
382 Allow the SUID / SGID state of an applet to be determined at runtime
383 by checking /etc/busybox.conf. (This is sort of a poor man's sudo.)
384 The format of this file is as follows:
386 APPLET = [Ssx-][Ssx-][x-] [USER.GROUP]
388 s: USER or GROUP is allowed to execute APPLET.
389 APPLET will run under USER or GROUP
390 (reagardless of who's running it).
391 S: USER or GROUP is NOT allowed to execute APPLET.
392 APPLET will run under USER or GROUP.
393 This option is not very sensical.
394 x: USER/GROUP/others are allowed to execute APPLET.
395 No UID/GID change will be done when it is run.
396 -: USER/GROUP/others are not allowed to execute APPLET.
398 An example might help:
401 su = ssx root.0 # applet su can be run by anyone and runs with
403 su = ssx # exactly the same
405 mount = sx- root.disk # applet mount can be run by root and members
406 # of group disk (but not anyone else)
407 # and runs with euid=0 (egid is not changed)
409 cp = --- # disable applet cp for everyone
411 The file has to be owned by user root, group root and has to be
412 writeable only by root:
413 (chown 0.0 /etc/busybox.conf; chmod 600 /etc/busybox.conf)
414 The busybox executable has to be owned by user root, group
415 root and has to be setuid root for this to work:
416 (chown 0.0 /bin/busybox; chmod 4755 /bin/busybox)
418 Robert 'sandman' Griebl has more information here:
419 <url: http://www.softforge.de/bb/suid.html >.
421 config FEATURE_SUID_CONFIG_QUIET
422 bool "Suppress warning message if /etc/busybox.conf is not readable"
424 depends on FEATURE_SUID_CONFIG
426 /etc/busybox.conf should be readable by the user needing the SUID,
427 check this option to avoid users to be notified about missing
431 bool "Support NSA Security Enhanced Linux"
433 select PLATFORM_LINUX
435 Enable support for SELinux in applets ls, ps, and id. Also provide
436 the option of compiling in SELinux applets.
438 If you do not have a complete SELinux userland installed, this stuff
439 will not compile. Specifially, libselinux 1.28 or better is
440 directly required by busybox. If the installation is located in a
441 non-standard directory, provide it by invoking make as follows:
442 CFLAGS=-I<libselinux-include-path> \
443 LDFLAGS=-L<libselinux-lib-path> \
446 Most people will leave this set to 'N'.
448 config FEATURE_PREFER_APPLETS
449 bool "exec prefers applets"
452 This is an experimental option which directs applets about to
453 call 'exec' to try and find an applicable busybox applet before
454 searching the PATH. This is typically done by exec'ing
456 This may affect shell, find -exec, xargs and similar applets.
457 They will use applets even if /bin/<applet> -> busybox link
458 is missing (or is not a link to busybox). However, this causes
459 problems in chroot jails without mounted /proc and with ps/top
460 (command name can be shown as 'exe' for applets started this way).
462 config BUSYBOX_EXEC_PATH
463 string "Path to BusyBox executable"
464 default "/proc/self/exe"
466 When Busybox applets need to run other busybox applets, BusyBox
467 sometimes needs to exec() itself. When the /proc filesystem is
468 mounted, /proc/self/exe always points to the currently running
469 executable. If you haven't got /proc, set this to wherever you
470 want to run BusyBox from.
472 # These are auto-selected by other options
474 config FEATURE_SYSLOG
475 bool #No description makes it a hidden option
478 # This option is auto-selected when you select any applet which may
479 # send its output to syslog. You do not need to select it manually.
481 config FEATURE_HAVE_RPC
482 bool #No description makes it a hidden option
485 # This is automatically selected if any of enabled applets need it.
486 # You do not need to select it manually.
493 bool "Build BusyBox as a static binary (no shared libs)"
496 If you want to build a static BusyBox binary, which does not
497 use or require any shared libraries, then enable this option.
498 This can cause BusyBox to be considerably larger, so you should
499 leave this option false unless you have a good reason (i.e.
500 your target platform does not support shared libraries, or
501 you are building an initrd which doesn't need anything but
504 Most people will leave this set to 'N'.
507 bool "Build BusyBox as a position independent executable"
511 Hardened code option. PIE binaries are loaded at a different
512 address at each invocation. This has some overhead,
513 particularly on x86-32 which is short on registers.
515 Most people will leave this set to 'N'.
518 bool "Force NOMMU build"
521 Busybox tries to detect whether architecture it is being
522 built against supports MMU or not. If this detection fails,
523 or if you want to build NOMMU version of busybox for testing,
524 you may force NOMMU build here.
526 Most people will leave this set to 'N'.
528 # PIE can be made to work with BUILD_LIBBUSYBOX, but currently
529 # build system does not support that
530 config BUILD_LIBBUSYBOX
531 bool "Build shared libbusybox"
533 depends on !FEATURE_PREFER_APPLETS && !PIE && !STATIC
535 Build a shared library libbusybox.so.N.N.N which contains all
538 This feature allows every applet to be built as a tiny
539 separate executable. Enabling it for "one big busybox binary"
540 approach serves no purpose and increases code size.
541 You should almost certainly say "no" to this.
543 ### config FEATURE_FULL_LIBBUSYBOX
544 ### bool "Feature-complete libbusybox"
545 ### default n if !FEATURE_SHARED_BUSYBOX
546 ### depends on BUILD_LIBBUSYBOX
548 ### Build a libbusybox with the complete feature-set, disregarding
549 ### the actually selected config.
551 ### Normally, libbusybox will only contain the features which are
552 ### used by busybox itself. If you plan to write a separate
553 ### standalone application which uses libbusybox say 'Y'.
555 ### Note: libbusybox is GPL, not LGPL, and exports no stable API that
556 ### might act as a copyright barrier. We can and will modify the
557 ### exported function set between releases (even minor version number
558 ### changes), and happily break out-of-tree features.
560 ### Say 'N' if in doubt.
562 config FEATURE_INDIVIDUAL
563 bool "Produce a binary for each applet, linked against libbusybox"
565 depends on BUILD_LIBBUSYBOX
567 If your CPU architecture doesn't allow for sharing text/rodata
568 sections of running binaries, but allows for runtime dynamic
569 libraries, this option will allow you to reduce memory footprint
570 when you have many different applets running at once.
572 If your CPU architecture allows for sharing text/rodata,
573 having single binary is more optimal.
575 Each applet will be a tiny program, dynamically linked
576 against libbusybox.so.N.N.N.
578 You need to have a working dynamic linker.
580 config FEATURE_SHARED_BUSYBOX
581 bool "Produce additional busybox binary linked against libbusybox"
583 depends on BUILD_LIBBUSYBOX
585 Build busybox, dynamically linked against libbusybox.so.N.N.N.
587 You need to have a working dynamic linker.
589 ### config BUILD_AT_ONCE
590 ### bool "Compile all sources at once"
593 ### Normally each source-file is compiled with one invocation of
595 ### If you set this option, all sources are compiled at once.
596 ### This gives the compiler more opportunities to optimize which can
597 ### result in smaller and/or faster binaries.
599 ### Setting this option will consume alot of memory, e.g. if you
600 ### enable all applets with all features, gcc uses more than 300MB
601 ### RAM during compilation of busybox.
603 ### This option is most likely only beneficial for newer compilers
604 ### such as gcc-4.1 and above.
606 ### Say 'N' unless you know what you are doing.
609 bool "Build with Large File Support (for accessing files > 2 GB)"
612 If you want to build BusyBox with large file support, then enable
613 this option. This will have no effect if your kernel or your C
614 library lacks large file support for large files. Some of the
615 programs that can benefit from large file support include dd, gzip,
616 cp, mount, tar, and many others. If you want to access files larger
617 than 2 Gigabytes, enable this option. Otherwise, leave it set to 'N'.
619 config CROSS_COMPILER_PREFIX
620 string "Cross Compiler prefix"
623 If you want to build BusyBox with a cross compiler, then you
624 will need to set this to the cross-compiler prefix, for example,
627 Note that CROSS_COMPILE environment variable or
628 "make CROSS_COMPILE=xxx ..." will override this selection.
630 Native builds leave this empty.
633 string "Path to sysroot"
636 If you want to build BusyBox with a cross compiler, then you
637 might also need to specify where /usr/include and /usr/lib
640 For example, BusyBox can be built against an installed
641 Android NDK, platform version 9, for ARM ABI with
643 CONFIG_SYSROOT=/opt/android-ndk/platforms/android-9/arch-arm
645 Native builds leave this empty.
648 string "Additional CFLAGS"
651 Additional CFLAGS to pass to the compiler verbatim.
654 string "Additional LDFLAGS"
657 Additional LDFLAGS to pass to the linker verbatim.
660 string "Additional LDLIBS"
663 Additional LDLIBS to pass to the linker with -l.
667 menu 'Debugging Options'
670 bool "Build BusyBox with extra Debugging symbols"
673 Say Y here if you wish to examine BusyBox internals while applets are
674 running. This increases the size of the binary considerably, and
675 should only be used when doing development. If you are doing
676 development and want to debug BusyBox, answer Y.
678 Most people should answer N.
680 config DEBUG_PESSIMIZE
681 bool "Disable compiler optimizations"
685 The compiler's optimization of source code can eliminate and reorder
686 code, resulting in an executable that's hard to understand when
687 stepping through it with a debugger. This switches it off, resulting
688 in a much bigger executable that more closely matches the source
692 bool "Build unit tests"
695 Say Y here if you want to build unit tests (both the framework and
696 test cases) as a Busybox applet. This results in bigger code, so you
697 probably don't want this option in production builds.
700 bool "Abort compilation on any warning"
703 Selecting this will add -Werror to gcc command line.
705 Most people should answer N.
708 prompt "Additional debugging library"
711 Using an additional debugging library will make BusyBox become
712 considerable larger and will cause it to run more slowly. You
713 should always leave this option disabled for production use.
717 This enables compiling with dmalloc ( http://dmalloc.com/ )
718 which is an excellent public domain mem leak and malloc problem
719 detector. To enable dmalloc, before running busybox you will
720 want to properly set your environment, for example:
721 export DMALLOC_OPTIONS=debug=0x34f47d83,inter=100,log=logfile
722 The 'debug=' value is generated using the following command
723 dmalloc -p log-stats -p log-non-free -p log-bad-space \
724 -p log-elapsed-time -p check-fence -p check-heap \
725 -p check-lists -p check-blank -p check-funcs -p realloc-copy \
728 Electric-fence support:
729 -----------------------
730 This enables compiling with Electric-fence support. Electric
731 fence is another very useful malloc debugging library which uses
732 your computer's virtual memory hardware to detect illegal memory
733 accesses. This support will make BusyBox be considerable larger
734 and run slower, so you should leave this option disabled unless
735 you are hunting a hard to find memory problem.
745 bool "Electric-fence"
751 menu 'Installation Options ("make install" behavior)'
754 prompt "What kind of applet links to install"
755 default INSTALL_APPLET_SYMLINKS
757 Choose what kind of links to applets are created by "make install".
759 config INSTALL_APPLET_SYMLINKS
762 Install applets as soft-links to the busybox binary. This needs some
763 free inodes on the filesystem, but might help with filesystem
764 generators that can't cope with hard-links.
766 config INSTALL_APPLET_HARDLINKS
769 Install applets as hard-links to the busybox binary. This might
770 count on a filesystem with few inodes.
772 config INSTALL_APPLET_SCRIPT_WRAPPERS
773 bool "as script wrappers"
775 Install applets as script wrappers that call the busybox binary.
777 config INSTALL_APPLET_DONT
780 Do not install applet links. Useful when you plan to use
781 busybox --install for installing links, or plan to use
782 a standalone shell and thus don't need applet links.
787 prompt "/bin/sh applet link"
788 default INSTALL_SH_APPLET_SYMLINK
789 depends on INSTALL_APPLET_SCRIPT_WRAPPERS
791 Choose how you install /bin/sh applet link.
793 config INSTALL_SH_APPLET_SYMLINK
796 Install /bin/sh applet as soft-link to the busybox binary.
798 config INSTALL_SH_APPLET_HARDLINK
801 Install /bin/sh applet as hard-link to the busybox binary.
803 config INSTALL_SH_APPLET_SCRIPT_WRAPPER
804 bool "as script wrapper"
806 Install /bin/sh applet as script wrapper that calls
812 string "BusyBox installation prefix"
815 Define your directory to install BusyBox files/subdirs in.
819 source libbb/Config.in
825 source archival/Config.in
826 source coreutils/Config.in
827 source console-tools/Config.in
828 source debianutils/Config.in
829 source editors/Config.in
830 source findutils/Config.in
831 source init/Config.in
832 source loginutils/Config.in
833 source e2fsprogs/Config.in
834 source modutils/Config.in
835 source util-linux/Config.in
836 source miscutils/Config.in
837 source networking/Config.in
838 source printutils/Config.in
839 source mailutils/Config.in
840 source procps/Config.in
841 source runit/Config.in
842 source selinux/Config.in
843 source shell/Config.in
844 source sysklogd/Config.in