[ANNOUNCEMENT] Updated: dash-

Steven Penny svnpenn@gmail.com
Sat Feb 25 17:09:00 GMT 2017

On Sat, 25 Feb 2017 11:46:08, cyg Simple wrote:
> If *your* script has a dependency to run using *dash* instead of *sh*
> then you _must_ use #!/bin/dash anyway.

I think you have a fundamental misunderstanding of what Dash is. Dash is a
minimal shell, similar to the "sh" defined by POSIX:


So saying "a dependency to run using *dash*" makes about as much sense as saying
"Cygwin has a dependency to run using Cygwin". 

> And what I _*I*_ don't want dash as /bin/sh? You see not everyone in the
> community will agree.

With respect to the community, yes of course you get a say. If the community
doesn’t agree on this we will continue to use Bash. However you do not get a say
with respect to the standard. The POSIX standard specified that /bin/sh is the
shell I have linked above. Bash is a superset of that, so by definition those
extra features are not defined or guaranteed to exist. When writing /bin/sh
scripts, you should be assuming the users /bin/sh only has those features
defined by POSIX. Example:

#!/bin/bash -> script that follows might have Bashisms
#!/bin/dash -> script that follows might have Dashisms (echo -n, local)
#!/bin/sh -> script that follows should be a POSIX script

> You can make the suggestion to those using your script to do so otherwise but
> forcing dash as /bin/sh worldwide isn't something you can actually do.

Yes we certainly can. Debian and Ubuntu have already done this.

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