Re: t5570 trap use in start/stop_git_daemon

[Joachim Schmitz <jojo@schmitz-digital.de>]

Jeff King <peff <at> peff.net> writes:

> 
> On Fri, Feb 13, 2015 at 02:44:03AM -0500, Jeff King wrote:
> 
> > On Thu, Feb 12, 2015 at 03:31:12PM -0500, Randall S. Becker wrote:
> > 
<snip> 
> Hmm, today I learned something new about ksh. Apparently when you use
> the "function" keyword to define a function like:
> 
>   function foo {
>     trap 'echo trapped' EXIT
>   }
>   echo before
>   foo
>   echo after
> 
> then the trap runs when the function exits! If you declare the same
> function as:
> 
>   foo() {
>     trap 'echo trapped' EXIT
>   }
> 
> it behaves differently. POSIX shell does not have the function keyword,
> of course, and we are not using it here. Bash _does_ have the function
> keyword, but seems to behave POSIX-y even when it is present. I.e.,
> running the first script:
> 
>   $ ksh foo.sh
>   before
>   trapped
>   after
> 
>   $ bash foo.sh
>   before
>   after
>   trapped
> 
>   $ dash foo.sh
>   foo.sh: 3: foo.sh: function: not found
>   foo.sh: 5: foo.sh: Syntax error: "}" unexpected
> 
> Switching to the second form, all three produce:
> 
>   before
>   after
>   trapped
> 
> I don't know if that is all helpful to your bug-tracking or analysis,
> but for whatever reason it looks like your ksh is using localized traps
> for both forms of function. But as far as I know, bash has never behaved
> that way (I just grepped its CHANGES file for mentions of trap and found
> nothing likely).
> 
> -Peff
> 

Both versions produce your first output on our platform

$ ksh foo1.sh
before
trapped
after
$ bash foo1.sh
before
after
trapped
$ ksh foo2.sh
before
trapped
after
$ bash foo2.sh
before
after
trapped
$

This might have been one (or even _the_) reason why we picked bash as our 
SHELL_PATH in config.mak.uname (I don't remember, it's more than 2 years 
ago), not sure which shell Randall's test used?

bye, Jojo