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      1 <html><head><title>toybox roadmap</title>
      2 <!--#include file="header.html" -->
      3 <title>Toybox Roadmap</title>
      4 
      5 <h2>Goals and use cases</h2>
      6 
      7 <p>We have several potential use cases for a new set of command line
      8 utilities, and are using those to determine which commands to implement
      9 for Toybox's 1.0 release.</p>
     10 
     11 <p>The most interesting standards are POSIX-2008 (also known as the Single
     12 Unix Specification version 4) and the Linux Standard Base (version 4.1).
     13 The main test harness including toybox in Aboriginal Linux and if that can
     14 build itself using the result to build Linux From Scratch (version 6.8).
     15 We also aim to replace Android's Toolbox.</p>
     16 
     17 <p>At a secondary level we'd like to meet other use cases. We've analyzed
     18 the commands provided by similar projects (klibc, sash, sbase, s6, embutils,
     19 nash, and beastiebox), along with various vendor configurations of busybox,
     20 and some end user requests.</p>
     21 
     22 <p>Finally, we'd like to provide a good replacement for the Bash shell,
     23 which was the first program Linux ever ran and remains the standard shell
     24 of Linux no matter what Ubuntu says. This doesn't mean including the full
     25 set of Bash 4.x functionality, but does involve {various,features} beyond
     26 posix.</p>
     27 
     28 <p>See the <a href=status.html>status page</a> for the combined list
     29 and progress towards implementing it.</p>
     30 
     31 <ul>
     32 <li><a href=#susv4>POSIX-2008/SUSv4</a></li>
     33 <li><a href=#sigh>Linux "Standard" Base</a></li>
     34 <li><a href=#dev_env>Development Environment</a></li>
     35 <li><a href=#android>Android Toolbox</a></li>
     36 <li><a href=#tizen>Tizen Core</a></li>
     37 <li>Miscelaneous: <a href=#klibc>klibc</a>, <a href=#glibc>glibc</a>,
     38 <a href=#sash>sash</a>, <a href=#sbase>sbase</a>, <a href=#s6>s6</a>...</li>
     39 </ul>
     40 
     41 <hr />
     42 <a name="standards">
     43 <h2>Use case: standards compliance.</h2>
     44 
     45 <h3><a name=susv4 /><a href="#susv4">POSIX-2008/SUSv4</a></h3>
     46 <p>The best standards are the kind that describe reality, rather than
     47 attempting to impose a new one.  (I.E. a good standard should document, not
     48 legislate.)</p>
     49 
     50 <p>The kind of standards which describe existing reality tend to be approved by
     51 more than one standards body, such ANSI and ISO both approving C.  That's why
     52 the IEEE POSIX committee's 2008 standard, the Single Unix Specification version
     53 4, and the Open Group Base Specification edition 7 are all the same standard
     54 from three sources.</p>
     55 
     56 <p>The <a href="http://pubs.opengroup.org/onlinepubs/9699919799/idx/utilities.html">"utilities"
     57 section</a>
     58 of these standards is devoted to the unix command line, and are the best such
     59 standard for our purposes.  (My earlier work on BusyBox was implemented with
     60 regard to SUSv3, an earlier version of this standard.)</p>
     61 
     62 <h3>Problems with the standard</h3>
     63 
     64 <p>Unfortunately, these standards describe a subset of reality, lacking any
     65 mention of commands such as init, login, or mount required to actually boot a
     66 system. It provides ipcrm and ipcs, but not ipcmk, so you can use System V IPC
     67 resources but not create them.</p>
     68 
     69 <p>These standards also contain a large number of commands that are
     70 inappropriate for toybox to implement in its 1.0 release.  (Perhaps some of
     71 these could be reintroduced in later releases, but not now.)</p>
     72 
     73 <p>Starting with the full "utilities" list, we first remove generally obsolete
     74 commands (compess ed ex pr uncompress uccp uustat uux), commands for the
     75 pre-CVS "SCCS" source control system (admin delta get prs rmdel sact sccs unget
     76 val what), fortran support (asa fort77), and batch processing support (batch
     77 qalter qdel qhold qmove qmsg qrerun qrls qselect qsig qstat qsub).</p>
     78 
     79 <p>Some commands are for a compiler toolchain (ar c99 cflow ctags cxref gencat
     80 iconv lex m4 make nm strings strip tsort yacc), which is outside of toybox's
     81 mandate and should be supplied externally.  (Again, some of these may be
     82 revisited later, but not for toybox 1.0.)</p>
     83 
     84 <p>Some commands are part of a command shell, and cannot be implemented as
     85 separate executables (alias bg cd command fc fg getopts hash jobs kill read
     86 type ulimit umask unalias wait).  These may be revisited as part of a built-in
     87 toybox shell, but are not exported into $PATH via symlinks.  (If you fork a
     88 child process and have it "cd" then exit, you've accomplished nothing.)</p>
     89 
     90 <p>A few other commands are judgement calls, providing command-line
     91 internationalization support (iconv locale localedef), System V inter-process
     92 communication (ipcrm ipcs), and cross-tty communication from the minicomputer
     93 days (talk mesg write).  The "pax" utility was supplanted by tar, "mailx" is
     94 a command line email client, and "lp" submits files for printing to... what
     95 exactly?  (cups?)  The standard defines crontab but not crond.</p>
     96 
     97 <p>Removing all of that leaves the following commands, which toybox should
     98 implement:</p>
     99 
    100 <blockquote><b>
    101 <span id=posix>
    102 at awk basename bc cal cat chgrp chmod chown cksum cmp comm cp
    103 csplit cut date dd df diff dirname du echo env expand expr false file find
    104 fold fuser getconf grep head id join kill link ln logger logname ls man
    105 mkdir mkfifo more mv newgrp nice nl nohup od paste patch pathchk printf ps
    106 pwd renice rm rmdir sed sh sleep sort split stty tabs tail tee test time
    107 touch tput tr true tty uname unexpand uniq unlink uudecode uuencode vi wc
    108 who xargs zcat
    109 </span>
    110 </b></blockquote>
    111 
    112 <h3><a name=sigh /><a href="#sigh">Linux Standard Base</a></h3>
    113 
    114 <p>One attempt to supplement POSIX towards an actual usable system was the
    115 Linux Standard Base. Unfortunately, the quality of this "standard" is
    116 fairly low.</p>
    117 
    118 <p>POSIX allowed its standards process to be compromised
    119 by leaving things out, thus allowing IBM mainframes and Windows NT to drive
    120 a truck through the holes and declare themselves compilant. But it means what
    121 they DID standardize tends to be respected.</p>
    122 
    123 <p>The Linux Standard Base's failure mode is different, they respond to
    124 pressure by including special-case crap, such as allowing Red Hat to shoehorn
    125 RPM on the standard even though all sorts of distros (Debian, Slackware, Arch,
    126 Gentoo) don't use it and probably never will. This means anything in the LSB is
    127 at best a suggestion: arbitrary portions of this standard are widely
    128 ignored.</p>
    129 
    130 <p>The LSB does specify a <a href=http://refspecs.linuxfoundation.org/LSB_4.1.0/LSB-Core-generic/LSB-Core-generic/cmdbehav.html>list of command line
    131 utilities</a>:</p>
    132 
    133 <blockquote><b>
    134 ar at awk batch bc chfn chsh col cpio crontab df dmesg du echo egrep 
    135 fgrep file fuser gettext grep groupadd groupdel groupmod groups 
    136 gunzip gzip hostname install install_initd ipcrm ipcs killall lpr ls 
    137 lsb_release m4 md5sum mknod mktemp more mount msgfmt newgrp od passwd 
    138 patch pidof remove_initd renice sed sendmail seq sh shutdown su sync 
    139 tar umount useradd userdel usermod xargs zcat
    140 </b></blockquote>
    141 
    142 <p>Where posix specifies one of those commands, LSB's deltas tend to be
    143 accomodations for broken tool versions which aren't up to date with the
    144 standard yet. (See <a href=http://refspecs.linuxfoundation.org/LSB_4.1.0/LSB-Core-generic/LSB-Core-generic/more.html>more</a> and <a href=http://refspecs.linuxfoundation.org/LSB_4.1.0/LSB-Core-generic/LSB-Core-generic/xargs.html>xargs</a>
    145 for examples.)</p>
    146 
    147 <p>Since we've already committed to using our own judgement to skip bits of
    148 POSIX, and LSB's "judgement" in this regard is purely bug workarounds to declare
    149 various legacy tool implementations "compliant", this means we're mostly
    150 interested in the set of tools that aren't specified in posix at all.</p>
    151 
    152 <p>Of these, gettext and msgfmt are internationalization, install_initd and
    153 remove_initd aren't present on ubuntu 10.04, lpr is out of scope, and
    154 lsb_release is a distro issue (it's a nice command, but the output of
    155 lsb_release -a is the name and version number of the linux distro you're
    156 running, which toybox doesn't know).</p>
    157 
    158 <p>This leaves:</p>
    159 
    160 <blockquote><b>
    161 <span id=lsb>
    162 chfn chsh dmesg egrep fgrep groupadd groupdel groupmod groups
    163 gunzip gzip hostname install killall md5sum
    164 mknod mktemp mount passwd pidof sendmail seq shutdown
    165 su sync tar umount useradd userdel usermod zcat
    166 </span>
    167 </b></blockquote>
    168 
    169 <hr />
    170 <a name="dev_env">
    171 <h2><a href="#dev_env">Use case: provide a self-hosting development environment</a></h2>
    172 
    173 <p>The following commands are enough to build the Aboriginal Linux development
    174 environment, boot it to a shell prompt, and build Linux From Scratch 6.8 under
    175 it. (Aboriginal Linux currently uses BusyBox for this, thus provides a
    176 drop-in test environment for toybox. We install both implementations side
    177 by side, redirecting the symlinks a command at a time until the older
    178 package is no longer used, and can be removed.)</p>
    179 
    180 <p>This use case includes running init scripts and other shell scripts, running
    181 configure, make, and install in each package, and providing basic command line
    182 facilities such as a text editor. (It does not include a compiler toolchain or
    183 C library, those are outside the scope of this project.)</p>
    184 
    185 <blockquote><b>
    186 <span id=development>
    187 bzcat cat cp dirname echo env patch rmdir sha1sum sleep sort sync
    188 true uname wc which yes zcat
    189 awk basename bzip2 chmod chown cmp cut date dd diff
    190 egrep expr find grep gzip head hostname id install ln ls
    191 mkdir mktemp mv od readlink rm sed sh tail tar touch tr uniq
    192 wget whoami xargs chgrp comm gunzip less logname man split
    193 tee test time bunzip2 chgrp chroot comm cpio dmesg
    194 dnsdomainname ftpd ftpget ftpput gunzip ifconfig init less
    195 logname losetup man mdev mount mountpoint nc pgrep pkill 
    196 pwd route split stat switch_root tac umount vi
    197 </span>
    198 </b></blockquote>
    199 
    200 <p>Note: Aboriginal Linux installs bash 2.05b as #!/bin/sh and its scripts
    201 require bash extensions not present in shells such as busybox ash.
    202 This means that toysh needs to supply several bash extensions _and_ work
    203 when called under the name "bash".</p>
    204 
    205 <p>The <a href=http://landley.net/aboriginal>Aboriginal Linux</a>
    206 self-bootstrapping build still uses the following busybox commands,
    207 not yet supplied by toybox:</p>
    208 
    209 <blockquote><p>
    210 ash awk bunzip2 bzip2 dd diff expr fdisk ftpd ftpget ftpput gunzip
    211 gzip less man pgrep ping pkill ps route sed sh sha512sum tar test tr unxz vi
    212 wget xzcat zcat</p></blockquote>
    213 
    214 <p>Many of those are in "pending". Most of the archive commands are needed
    215 because busybox tar doesn't call external versions. The remaining "difficult"
    216 commands are vi, awk, and ash.</p>
    217 
    218 <hr />
    219 <h2><a name=android /><a href="#android">Use case: Replacing Android Toolbox</a></h2>
    220 
    221 <p>Android has a policy against GPL in userspace, so even though BusyBox
    222 predates Android by many years, they couldn't use it. Instead they grabbed
    223 an old version of ash and implemented their own command line utility set
    224 called "toolbox". ash was later replaced by
    225 <a href="https://www.mirbsd.org/mksh.htm">mksh</a>; toolbox is being
    226 replaced by toybox.</p>
    227 
    228 <p>Toolbox doesn't have its own repository, instead it's part of Android's
    229 <a href=https://android.googlesource.com/platform/system/core>system/core
    230 git repository</a>.</p>
    231 
    232 <h3>Toolbox commands:</h3>
    233 
    234 <p>According to <a href=https://android.googlesource.com/platform/system/core/+/master/toolbox/Android.mk>
    235 system/core/toolbox/Android.mk</a> the toolbox directory builds the
    236 following commands:</p>
    237 
    238 <blockquote><b>
    239 dd du df getevent iftop ioctl ionice log ls
    240 lsof mount nandread newfs_msdos ps prlimit renice
    241 sendevent start stop top uptime watchprops
    242 </b></blockquote>
    243 
    244 <h3>Other Android core commands</h3>
    245 
    246 <p>Other than the toolbox directory, the currently interesting
    247 subdirectories in the core repository are gpttool, init,
    248 logcat, logwrapper, mkbootimg, reboot, and run-as.</p>
    249 
    250 <ul>
    251 <li><b>gpttool</b> - subset of fdisk</li>
    252 <li><b>init</b> - Android's PID 1</li>
    253 <li><b>logcat</b> - read android log format</li>
    254 <li><b>logwrapper</b> - redirect stdio to android log</li>
    255 <li><b>mkbootimg</b> - create signed boot image</li>
    256 <li><b>reboot</b> - Android's reboot(1)</li>
    257 <li><b>run-as</b> - subset of sudo</li>
    258 </ul>
    259 
    260 <p>Almost all of these reinvent an existing wheel with less functionality and a
    261 different user interface. We may want to provide that interface, but
    262 implementing the full commands (fdisk, init, and sudo) come first.</p>
    263 
    264 <p>Also, gpttool and mkbootimg are install tools.
    265 These aren't a priority if android wants to use its own
    266 bespoke code to install itself.</p>
    267 
    268 <h3>Analysis</h3>
    269 
    270 <p>For reference, combining everything listed above, we get:</p>
    271 
    272 <blockquote><b>
    273 dd du df getevent gpttool iftop init ioctl ionice
    274 log logcat logwrapper ls lsof mkbootimg mount nandread
    275 newfs_msdos ps prlimit reboot renice run-as
    276 sendevent start stop top uptime watchprops
    277 </b></blockquote>
    278 
    279 <p>We may eventually implement all of that, but for toybox 1.0 we need to
    280 focus a bit. For our first pass, let's ignore selinux [note: the android
    281 guys submitted selinux code to us and we merged it],
    282 and grab just logcat and logwrapper from the "core"
    283 commands (since the rest have some full/standard version providing that
    284 functionality, which we can implement a shim interface for later).</p>
    285 
    286 <p>This means toybox should implement (or finish implementing):</p>
    287 <blockquote><b>
    288 <span id=toolbox>
    289 dd du df getevent iftop ioctl ionice log logcat logwrapper ls lsof
    290 mount nandread newfs_msdos ps prlimit renice schedtop sendevent
    291 smd start stop top uptime watchprops
    292 </span>
    293 </b></blockquote>
    294 
    295 <hr />
    296 <h2><a name=tizen /><a href="#tizen">Use case: Tizen Core</a></h2>
    297 
    298 <p>The Tizen project has expressed a desire to eliminate GPLv3 software
    299 from its core system, and is installing toybox as
    300 <a href=https://wiki.tizen.org/wiki/Toybox>part of this process</a>.</p>
    301 
    302 <p>They have a fairly long list of new commands they'd like to see in toybox:</p>
    303 
    304 <blockquote><b>
    305 <span id=tizen>
    306 arch base64 users dir vdir unexpand shred join csplit
    307 hostid nproc runcon sha224 sha256 sha384 sha512 sha3 mkfs.vfat fsck.vfat 
    308 dosfslabel uname stdbuf pinky diff3 sdiff zcmp zdiff zegrep zfgrep zless zmore
    309 </span>
    310 </b></blockquote>
    311 
    312 <p>In addition, they'd like to use several commands currently in pending:</p>
    313 
    314 <blockquote><b>
    315 <span id=tizen>
    316 tar diff printf wget rsync fdisk vi less tr test stty fold expr dd
    317 </span>
    318 </b></blockquote>
    319 
    320 <p>Also, tizen uses a different Linux Security Module called SMACK, so
    321 many of the SELinux options ala ls -Z need smack alternatives in an
    322 if/else setup.</p>
    323 
    324 <hr /><a name=klibc />
    325 <h2>klibc:</h2>
    326 
    327 <p>Long ago some kernel developers came up with a project called
    328 <a href=http://en.wikipedia.org/wiki/Klibc>klibc</a>.
    329 After a decade of development it still has no web page or HOWTO,
    330 and nobody's quite sure if the license is BSD or GPL. It inexplicably
    331 <a href=http://www.infoworld.com/d/data-center/perl-isnt-going-anywhere-better-or-worse-211580>requires perl to build</a>, and seems like an ideal candidate for
    332 replacement.</p>
    333 
    334 <p>In addition to a C library even less capable than bionic (obsoleted by
    335 musl), klibc builds a random assortment of executables to run init scripts
    336 with. There's no multiplexer command, these are individual executables:</p>
    337 
    338 <blockquote><p>
    339 cat chroot cpio dd dmesg false fixdep fstype gunzip gzip halt ipconfig kill
    340 kinit ln losetup ls minips mkdir mkfifo mknodes
    341 mksyntax mount mv nfsmount nuke pivot_root poweroff readlink reboot resume
    342 run-init sh sha1hash sleep sync true umount uname zcat
    343 </p></blockquote>
    344 
    345 <p>To get that list, build klibc according to the instructions (I
    346 <a href=http://landley.net/notes-2013.html#23-01-2013>looked at</a> version
    347 2.0.2 and did cd klibc-*; ln -s /output/of/kernel/make/headers_install
    348 linux; make) then <b>echo $(for i in $(find . -type f); do file $i | grep -q
    349 executable && basename $i; done | grep -v '[.]g$' | sort -u)</b> to find
    350 executables, then eliminated the *.so files and *.shared duplicates.</p>
    351 
    352 <p>Some of those binaries are build-time tools that don't get installed,
    353 which removes mknodes, mksyntax, sha1hash, and fixdep from the list.
    354 (And sha1hash is just an unpolished sha1sum anyway.)</p>
    355 
    356 <p>The run-init command is more commonly called switch_root, nuke is just
    357 "rm -rf -- $@", and minips is more commonly called "ps". I'm not doing aliases
    358 for the oddball names.</p>
    359 
    360 <p>Yet more stale forks of dash and gzip sucked in here (see "dubious
    361 license terms" above), adding nothing to the other projects we've looked at.
    362 But we still need sh, gunzip, gzip, and zcat to replace this package.</p>
    363 
    364 <p>By the time I did the analysis toybox already had cat, chroot, dmesg, false,
    365 kill, ln, losetup, ls, mkdir, mkfifo, readlink, rm, switch_root, sleep, sync,
    366 true, and uname.</p>
    367 
    368 <p>The low hanging fruit is cpio, dd, ps, mv, and pivot_root.</p>
    369 
    370 <p>The "kinit" command is another gratuitous rename, it's init running as PID 1.
    371 The halt, poweroff, and reboot commands work with it.</p>
    372 
    373 <p>I've got mount and umount queued up already, fstype and nfsmount go with
    374 those. (And probably smbmount and p9mount, but this hasn't got one. Those
    375 are all about querying for login credentials, probably workable into the
    376 base mount command.)</p>
    377 
    378 <p>The ipconfig command here has a built in dhcp client, so it's ifconfig
    379 and dhcpcd and maybe some other stuff.</p>
    380 
    381 <p>The resume command is... weird. It finds a swap partition and reads data
    382 from it into a /proc file, something the kernel is capable of doing itself.
    383 (Even though the klibc author
    384 <a href=http://www.zytor.com/pipermail/klibc/2006-June/001748.html>attempted
    385 to remove</a> that capability from the kernel, current kernel/power/hibernate.c
    386 still parses "resume=" on the command line). And yet various distros seem to
    387 make use of klibc for this.
    388 Given the history of swsusp/hibernate (and 
    389 <a href=http://lwn.net/Articles/333007>TuxOnIce</a>
    390 and <a href=http://lwn.net/Articles/242107>kexec jump</a>) I've lost track
    391 of the current state of the art here. Ah, Documentation/power/userland-swsusp.txt
    392 has the API docs, and <a href=http://suspend.sf.net>here's a better
    393 tool</a>...</p>
    394 
    395 <p>So the list of things actually in klibc are:</p>
    396 
    397 <blockquote><b>
    398 <span id=klibc_cmd>
    399 cat chroot dmesg false kill ln losetup ls mkdir mkfifo readlink rm switch_root
    400 sleep sync true uname
    401 
    402 cpio dd ps mv pivot_root
    403 mount nfsmount fstype umount
    404 sh gunzip gzip zcat
    405 kinit halt poweroff reboot
    406 ipconfig
    407 resume
    408 </span>
    409 </b></blockquote>
    410 
    411 <hr />
    412 <a name=glibc />
    413 <h2>glibc</h2>
    414 
    415 <p>Rather a lot of command line utilities come bundled with glibc:</p>
    416 
    417 <blockquote><b>
    418 catchsegv getconf getent iconv iconvconfig ldconfig ldd locale localedef
    419 mtrace nscd rpcent rpcinfo tzselect zdump zic
    420 </b></blockquote>
    421 
    422 <p>Of those, musl libc only implements ldd.</p>
    423 
    424 <p>catchsegv is a rudimentary debugger, probably out of scope for toybox.</p>
    425 
    426 <p>iconv has been <a href="#susv4">previously discussed</a>.</p>
    427 
    428 <p>iconvconfig is only relevant if iconv is user-configurable; musl uses a
    429 non-configurable iconv.</p>
    430 
    431 <p>getconf is a posix utility which displays several variables from 
    432 unistd.h; it probably belongs in the development toolchain.</p>
    433 
    434 <p>getent handles retrieving entries from passwd-style databases
    435 (in a rather lame way) and is trivially replacable by grep.</p>
    436 
    437 <p>locale was discussed under <a href=#susv4>posix</a>.
    438 localedef compiles locale definitions, which musl currently does not use.</p>
    439 
    440 <p>mtrace is a perl script to use the malloc debugging that glibc has built-in;
    441 this is not relevant for musl, and would necessarily vary with libc. </p>
    442 
    443 <p>nscd is a name service caching daemon, which is not yet relevant for musl.
    444 rpcinfo and rpcent are related to rpc, which musl does not include.</p>
    445 
    446 <p>The remaining commands involve glibc's bundled timezone database,
    447 which seems to be derived from the <a href=http://www.iana.org/time-zones>IANA
    448 timezone database</a>. Unless we want to maintain our own fork of the
    449 standards body's database like glibc does, these are of no interest,
    450 but for completeness:</p>
    451 
    452 <p>tzselect outputs a TZ variable correponding to user input. 
    453 The documentation does not indicate how to use it in a script, but it seems
    454 that Debian may have done so.
    455 zdump prints current time in each of several timezones, optionally
    456 outputting a great deal of extra information about each timezone.
    457 zic converts a description of a timezone to a file in tz format.</p>
    458 
    459 <p>None of glibc's bundled commands are currently of interest to toybox.</p>
    460 
    461 </b></blockquote>
    462 
    463 <hr />
    464 <a name=sash />
    465 <h2>Stand-Alone Shell</h2>
    466 
    467 <p>Wikipedia has <a href=http://en.wikipedia.org/wiki/Stand-alone_shell>a good
    468 summary of sash</a>, with links. The original Stand-Alone Shell project reached
    469 a stopping point, and then <a href=http://www.baiti.net/sash>"sash plus
    470 patches"</a> extended it a bit further. The result is a megabyte executable
    471 that provides 40 commands.</p>
    472 
    473 <p>Sash is a shell with built-in commands. It doesn't have a multiplexer
    474 command, meaning "sash ls -l" doesn't work (you have to go "sash -c 'ls -l'").
    475 </p>
    476 
    477 <p>The list of commands can be obtained via building it and doing
    478 "echo help | ./sash | awk '{print $1}' | sed 's/^-//' | xargs echo", which
    479 gives us:</p>
    480 
    481 <blockquote><b>
    482 alias aliasall ar cd chattr chgrp chmod chown cmp cp chroot dd echo ed exec
    483 exit file find grep gunzip gzip help kill losetup losetup ln ls lsattr mkdir
    484 mknod more mount mv pivot_root printenv prompt pwd quit rm rmdir setenv source
    485 sum sync tar touch umask umount unalias where
    486 </b></blockquote>
    487 
    488 <p>Plus sh because it's a shell. A dozen or so commands can only sanely be
    489 implemented as shell builtins (alias aliasall cd exec exit prompt quit setenv
    490 source umask unalias), where is an alias for which, and at triage time toybox
    491 already has chgrp, chmod, chown, cmp, cp, chroot, echo, help, kill, losetup,
    492 ln, ls, mkdir, mknod, printenv, pwd, rm, rmdir, sync, and touch.</p>
    493 
    494 <p>This leaves:</p>
    495 
    496 <blockquote><b>
    497 <span id=sash_cmd>
    498 ar chattr dd ed file find grep gunzip gzip lsattr more mount mv pivot_root
    499 sh sum tar umount
    500 </span>
    501 </b></blockquote>
    502 
    503 <p>(For once, this project doesn't include a fork of gzip, instead
    504 it sucks in -lz from the host.)</p>
    505 
    506 <hr />
    507 <a name=sbase />
    508 <h2>sbase:</h2>
    509 
    510 <p>It's <a href=http://git.suckless.org/sbase>on suckless</a>. So far it's
    511 implemented:</p>
    512 
    513 <blockquote><p>
    514 <span id=sbase_cmd>
    515 basename cat chmod chown cksum cmp cp date dirname echo false fold grep head
    516 kill ln ls mc mkdir mkfifo mv nl nohup pwd rm seq sleep sort tail tee test
    517 touch true tty uname uniq wc yes
    518 </span>
    519 </p></blockquote>
    520 
    521 <p>And has a TODO list:</p>
    522 
    523 <blockquote><p>
    524 <span id=sbase_cmd>
    525 cal chgrp chvt comm cut df diff du env expand expr id md5sum nice paste
    526 printenv printf readlink rmdir seq sha1sum split sync test tr unexpand unlink
    527 who
    528 </span>
    529 </p></blockquote>
    530 
    531 <p>At triage time, of the first list I still need to do: fold grep mc mv nl. Of
    532 the second list: diff expr paste printf split test tr unexpand who.</p>
    533 
    534 <hr />
    535 <a name=s6 />
    536 <h2>s6</h2>
    537 
    538 <p>The website <a href=http://skarnet.org/software/>skarnet</a> has a bunch
    539 of small utilities as part of something called "s6". This includes the
    540 <a href=http://skarnet.org/software/s6-portable-utils>s6-portabile-utils</a>
    541 and the <a href=http://skarnet.org/software/s6-linux-utils>s6-linux-utils</a>.
    542 </p>
    543 
    544 <p>Both packages rely on multiple bespoke external libraries without which
    545 they can't compile. The source is completely uncommented and doesn't wrap at
    546 80 characters. Doing a find for *.c files brings up the following commands:</p>
    547 
    548 <blockquote><b>
    549 <span id=s6>
    550 basename cat chmod chown chroot clock cut devd dirname echo env expr false
    551 format-filter freeramdisk grep halt head hiercopy hostname linkname ln
    552 logwatch ls maximumtime memoryhog mkdir mkfifo mount nice nuke pause
    553 pivotchroot poweroff printenv quote quote-filter reboot rename rmrf sleep
    554 sort swapoff swapon sync tail test touch true umount uniquename unquote
    555 unquote-filter update-symlinks
    556 </span>
    557 </b></blockquote>
    558 
    559 <p>Triage: memoryhog isn't even listed on the website nor does it have
    560 a documentation file, clock seems like a subset
    561 of date, devd is some sort of netlink wrapper that spawns its command line
    562 every time it gets a message (maybe this is meant to implement part of
    563 udev/mdev?), format-filter is sort of awk's '{print $2}' function split out
    564 into its own command, hiercopy a subset of "cp -r", maximumtime is something
    565 I implemented as a shell script (more/timeout.sh in Aboriginal Linux),
    566 nuke isn't the same as klibc (this one's "kill SIG -1" only with hardwared
    567 SIG options), pause is a program that literally waits to be killed (I
    568 generally sleep 999999999 which is a little over 30 years),
    569 pivotchroot is a subset of switch_root, rmrf is rm -rf...</p>
    570 
    571 <p>I see "nuke" resurface, and if "rmrf" wasn't also here I might think
    572 klibc had a point.</b>
    573 
    574 <blockquote>
    575 basename cat chmod chown chroot cut dirname echo env expr false
    576 freeramdisk grep halt head hostname linkname ln
    577 logwatch ls mkdir mkfifo mount nice
    578 pivotchroot poweroff printenv quote quote-filter reboot rename sleep
    579 sort swapoff swapon sync tail test touch true umount uniquename unquote
    580 unquote-filter update-symlinks
    581 </blockquote>
    582 
    583 
    584 <hr />
    585 <a name=nash />
    586 <h2>nash:</h2>
    587 
    588 <p>Red Hat's nash was part of its "mkinitrd" package, replacement for a shell
    589 and utilities on the boot floppy back in the 1990's (the same general idea
    590 as BusyBox, developed independently). Red Hat discontinued nash development
    591 in 2010, replacing it with dracut (which collects together existing packages,
    592 including busybox).</p>
    593 
    594 <p>I couldn't figure out how to beat source code out of
    595 <a href=http://pkgs.fedoraproject.org/git/mkinitrd>Fedora's current git</a>
    596 repository. The last release version that used it was Fedora Core 12
    597 which has <a href=http://archive.fedoraproject.org/pub/archive/fedora/linux/releases/12/Fedora/source/SRPMS/mkinitrd-6.0.93-1.fc12.src.rpm>a source rpm</a>
    598 that can be unwound with "rpm2cpio mkinitrd.src.rpm | cpio -i -d -H newc
    599 --no-absolute-filenames" and in there is a mkinitrd-6.0.93.tar.bz2 which
    600 has the source.</p>
    601 
    602 <p>In addition to being a bit like a command shell, the nash man page lists the
    603 following commands:</p>
    604 
    605 <blockquote><p>
    606 access echo find losetup mkdevices mkdir mknod mkdmnod mkrootdev mount
    607 pivot_root readlink raidautorun setquiet showlabels sleep switchroot umount
    608 </p></blockquote>
    609 
    610 <p>Oddly, the only occurrence of the string pivot_root in the nash source code
    611 is in the man page, the command isn't there. (It seems to have been removed
    612 when the underscoreless switchroot went in.)</p>
    613 
    614 <p>A more complete list seems to be the handlers[] array in nash.c:</p>
    615 
    616 <blockquote><p>
    617 access buildEnv cat cond cp daemonize dm echo exec exit find kernelopt
    618 loadDrivers loadpolicy mkchardevs mkblktab mkblkdevs mkdir mkdmnod mknod
    619 mkrootdev mount netname network null plymouth hotplug killplug losetup
    620 ln ls raidautorun readlink resume resolveDevice rmparts setDeviceEnv
    621 setquiet setuproot showelfinterp showlabels sleep stabilized status switchroot
    622 umount waitdev
    623 </p></blockquote>
    624 
    625 <p>This list is nuts: "plymouth" is an alias for "null" which is basically
    626 "true" (which thie above list doesn't have). Things like buildEnv and
    627 loadDrivers are bespoke Red Hat behavior that might as well be hardwired in
    628 to nash's main() without being called.</p>
    629 
    630 <p>Instead of eliminating items
    631 from the list with an explanation for each, I'm just going to cherry pick
    632 a few: the device mapper (dm, raidautorun) is probably interesting,
    633 hotplug (may be obsolete due to kernel changes that now load firmware
    634 directly), and another "resume" ala klibc.</p>
    635 
    636 <p>But mostly: I don't care about this one. And neither does Red Hat anymore.</p>
    637 
    638 <p>Verdict: ignore</p>
    639 
    640 <hr />
    641 <a name=beastiebox />
    642 <h2>Beastiebox</h2>
    643 
    644 <p>Back in 2008, the BSD guys vented some busybox-envy
    645 <a href=http://beastiebox.sourceforge.net>on sourceforge</a>. Then stopped.
    646 Their repository is still in CVS, hasn't been touched in years, it's a giant
    647 hairball of existing code sucked together. (The web page says the author
    648 is aware of crunchgen, but decided to do this by hand anyway. This is not
    649 a collection of new code, it's a katamari of existing code rolled up in a
    650 ball.)</p>
    651 
    652 <p>Combining the set of commands listed on the web page with the set of
    653 man pages in the source gives us:</P>
    654 
    655 <blockquote><p>
    656 [ cat chmod cp csh date df disklabel dmesg echo ex fdisk fsck fsck_ffs getty
    657 halt hostname ifconfig init kill less lesskey ln login ls lv mksh more mount
    658 mount_ffs mv pfctl ping poweroff ps reboot rm route sed sh stty sysctl tar test
    659 traceroute umount vi wiconfig
    660 </p></blockquote>
    661 
    662 <p>Apparently lv is the missing link ed and vi, copyright 1982-1997 (do not
    663 want), ex is another obsolete vi mode, lesskey is "used to
    664 specify a set of key bindings to be used with less", and csh is a shell they
    665 sucked in, [ is an alias for test. Several more bsd-isms that don't have Linux
    666 equivalents (even in the ubuntu "install this package" search) are
    667 disklabel, fsck_ffs, mount_ffs, and pfctl. And wiconfig is a wavelan interface
    668 network card driver utility. Subtracting all that and the commands toybox
    669 already implements at triage time, we get:</p>
    670 
    671 <blockquote><p>
    672 <span id=beastiebox_cmd>
    673 fdisk fsck getty halt ifconfig init kill less mksh more mount mv ping poweroff
    674 ps reboot route sed sh stty sysctl tar test traceroute umount vi
    675 </span>
    676 </p></blockquote>
    677 
    678 <p>Not a hugely interesting list, but eh.</p>
    679 
    680 <p>Verdict: ignore</p>
    681 
    682 <hr />
    683 <a name=BsdBox />
    684 <h2>BsdBox</h2>
    685 
    686 <p>Somebody decided to do a <a href=https://wiki.freebsd.org/AdrianChadd/BsdBox>multicall binary for freebsd</a>.</p>
    687 
    688 <p>They based it on crunchgen, a tool that glues existing programs together
    689 into an archive and uses the name to execute the right one. It has no
    690 simplification or code sharing benefits whatsoever, it's basically an
    691 archiver that produces executables.</p>
    692 
    693 <p>That's about where I stopped reading.</p>
    694 
    695 <p>Verdict: ignore.</p>
    696 
    697 <hr />
    698 <a name=slowaris />
    699 <h2>OpenSolaris Busybox</h2>
    700 
    701 <p>Somebody <a href=http://hub.opensolaris.org/bin/view/Project+busybox/>wrote
    702 a wiki page</a> saying that Busybox for OpenSolaris would be a good idea.</p>
    703 
    704 <p>The corresponding "files" tab is an auto-generated stub. The project never
    705 even got as far as suggesting commands to include before Oracle discontinued
    706 OpenSolaris.</p>
    707 
    708 <p>Verdict: ignore.</p>
    709 
    710 <hr />
    711 <h2>Requests:</h2>
    712 
    713 <p>The following additional commands have been requested (and often submitted)
    714 by various users:</p>
    715 <blockquote><b>
    716 <span id=request>
    717 dig freeramdisk getty halt hexdump hwclock klogd modprobe ping ping6 pivot_root
    718 poweroff readahead rev sfdisk sudo syslogd taskset telnet telnetd tracepath
    719 traceroute unzip usleep vconfig zip free login modinfo unshare netcat help w
    720 ntpd iwconfig iwlist rdate
    721 dos2unix unix2dos catv clear
    722 pmap realpath setsid timeout truncate
    723 mkswap swapon swapoff
    724 count oneit fstype
    725 acpi blkid eject pwdx
    726 sulogin rfkill bootchartd
    727 arp makedevs sysctl killall5 crond crontab deluser last mkpasswd watch
    728 ipaddr iplink iproute blockdev rpm2cpio arping brctl dumpleases fsck
    729 tcpsvd tftpd
    730 factor fallocate fsfreeze inotifyd lspci nbd-client partprobe strings
    731 base64 mix
    732 </span>
    733 </b></blockquote>
    734 
    735 <!-- #include "footer.html" -->
    736 
    737