Re: -e does not take effects in subshell

[Chet Ramey]

On 8/20/15 8:38 PM, Linda Walsh wrote:
> 
> 
> Chet Ramey wrote:
>>> The earlier spec had -e only exit a script if a *simple* (external)
>>> command failed.  It didn't include builtins nor functions.
>>
>> This is not; builtins and functions are simple commands.
> ---
> The builtins are _complex_ binary blobs that replace external commands.
> 
> Functions are a collection of many commands.  They are not a single,
> simple statement.  I remember using their return value in some cases.

`Simple command' is a specific term with a specific meaning.  It doesn't
have anything to do with perceived implementation complexity.

> 
> With the change, I couldn't run a func and have it return the
> value in $? (1 byte, I know) -- but about 128x as flexible as "ok"/"die"
> (i.e. any non-zero value triggers the behavior
> now, but before, it didn't).

That's fine, even clever, but fundamentally incompatible with the idea
that 0 means success and everything else means failure.

> My simplistic view was that -e was there to auto-exit if an external
> command failed because they are "out of your control".

That's an incomplete view.

-- 
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, ITS, CWRU    chet@case.edu    http://cnswww.cns.cwru.edu/~chet/