Tip: Try bosh as a fully POSIX compatible system shell!

[mv]

Up to now, linux had no fully POSIX compatible system shell. ^1

This changed from today! ^2

bosh is a shell which aims for POSIX compatibility and speed, and it has full multicharacter support ^3
Like dash, also bosh has some features which go beyond POSIX and which appear necessary for proper programming (e.g. "local" or "test ... -nt ...").

In particular, it should run nicely as a system shell and might even speed up your boot process and ./configure runs!

If you are interested, install >=app-shells/schily-tools-2016.08.01-r1 from the mv overlay (available over layman) with SCHILYTOOLS=bosh (i.e. USE=schilytools_bosh) being set.
If you want to try it as a system shell make /bin/sh a symlink to bosh (or use app-select/eselect-sh) ^4

The upstream author is highly interested in your feedback (and in my experience he is very responsive).

You can use this thread for reporting.


Footnotes:

1. For instance, bash, ksh, zsh - although they are good shells - do not even have the aim to be fully POSIX compatible.
   Some old Bourne shells (e.g. heirloom-sh) do not obey modern POSIX standards at all.
   dash strives for POSIX compatibility, but it currently fails due to lack of multicharacter support. Moreover, it accepts some code which should better not be accepted when you want to test for portable code (e.g. writing to non-opened streams).
   
2. bosh passed a major praxis test today: As a system shell, it currently runs a highly shell-script-oriented system (including openrc, netifrc, openresolv, keychain, ...) without any issues.
   
3. You can check whether your shell supports it by e.g.

   Code:

   printf '"%.4b"\n' löööööööööö

   or

   Code:

   IFS=ö; var=lölöl; echo $var

   
   
4. If you want to use bosh as a system shell, it is currently strongly recommended to emerge app-shells/schily-tools with USE=posix being set, for otherwise it might happen in some cases that bosh does not start in posix mode.

[audiodef]

Nice. Following.
_________________
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[schily]

I am not sure whether this is obvious from reading the original article, but the shell in question is based on the original Bourne Shell sources.

So the new code is based on 40 year old mature code and has been enhanced to support the POSIX shell features.

Even though the code is still not huge, the current source code is 4x the size of the Svr4 Bourne Shell from 1989.

[pun_guin]

I installed schily-tools from the slightly more up-to-date spikyatlinux overlay. The bosh command works. However, I cannot set it as "the default shell" - eselect sh list only ever finds the bash.
Has this functionality been removed?
_________________
I already use the new Genthree.

[mv]

[Dr.Willy]

[pun_guin]

[depontius]

When I switched "/bin/sh -> /bin/dash" it was because I'd read that dash was faster/leaner because it was a scripting shell, not having extra command-line functionality. My sessions still use /bin/bash as the command shell.

It sounds like /bin/bosh might be as much command-line shell as it is a scripting shell. Can you comment on functionality / speed trade-offs?
_________________
.sigs waste space and bandwidth

[mv]

[pun_guin]

IMO, using /etc/shells will not make sense here since they don't necessarily have to be POSIX shells.
_________________
I already use the new Genthree.

[mv]

[mv]

[pun_guin]

eselect-sh literally asks for a POSIX shell though. That's a second bug then.
_________________
I already use the new Genthree.

[szatox]