Vladimir N. Oleynik wrote:
>Erik Andersen wrote:
>
>>On Tue Jul 03, 2001 at 02:17:06PM -0400, David Douthitt wrote:
>>
>>>I've followed the discussion (somewhat) on different shells. I'm
>>>wondering what the difference is, and in particular, is ash going to
>>>absorbed into busybox or what?
>>>
>>>What are the differences between:
>>>
>>>* ash
>>>* hush
>>>* lash
>>>
>>>Any others I missed? (probably...)
>>>
>>In cvs we currently have lash, hush, msh, ash. For all size comparisons
>>below, I am leaving BB_FEATURE_COMMAND_EDITING disabled. Enabling it will
>>add about 8k to the size of each shell.
>>
>>lash: very small (adds just 10k) and quite usable as a command prompt, but it
>> is not suitable for any but the most trivial scripting since it does not
>> understand Bourne shell grammer. It does handle pipes, redirects, and
>> job control though. Adding in command editing makes it quite nice as
>> a command prompt.
>>
>>hush: Also quite small (just 18k) and it has very complete Bourne shell grammer.
>> It handles if/then/else/fi just fine, but doesn't handle loops like for/do/done
>> or case/esac and such. It also currently has a problem with job control.
>>
>>msh: The minix shell (adds just 30k) is quite complete and handles things like
>> for/do/done, case/esac and all the things you expect a Bourne shell to do. It
>> is not always pedantically correct about Bourne shell grammer (try running
>> the shell testscript, tests/sh.testcases, on it and compare vs bash), but for
>> most things it works quite well. It also uses only vfork, so it can be used
>> on uClinux systems. I just added this, so there is still room to shrink
>> it further...
>>
>>ash: This adds about 60k in the default configuration (I need to review vodz'
>> latest update, perhaps he has made it smaller again) and is the most complete
>> and most correct shell included with busybox. This was also recently added,
>> and both Vladimir and I have been working on it. There are a number of
>> configurable things at the top of ash.c as well. The Posix math stuff is
>> currently disabled, but I intend to fix it up when I get some time.
>>
>>Both msh and ash were very recently added to CVS, and so neither of these
>>shells supports the STANDALONE_SHELL option yet.
>>
So if busybox ash had math support would it be a posix compatable shell, or would
there be other issues as well ?
The root disk of debian boot floppies has ash from the deb (which is 85kB) as opposed
to ash from busybox, which from current CVS adds 67kB.
boot floppies expects a posix compatable shell for various scripts, debootstrap being
one of them.
Glenn
--
To UNSUBSCRIBE, email to [EMAIL PROTECTED]
with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
