Re: 4.3.11 TRAPEXIT() on cygwin

[Mikael Magnusson <mikachu@gmail.com>]

On 11 January 2011 04:25, Mikael Magnusson <mikachu@gmail.com> wrote:
>>    When a subshell is entered, traps that are not being ignored shall
>>    be set to the default actions, except in the case of a command
>>    substitution containing only a single trap command, when the traps
>>    need not be altered.
>
> Ah, the manpage says this
>       ( list )
>              Execute  list  in a subshell.  Traps set by the trap
> builtin are reset
>              to their default values while executing list.
>
> and it is true:
> % trap 'echo hello >&2' EXIT
> % a=$(ls)
> % TRAPEXIT() { echo function hello >&2 }
> % a=$(ls)
> function hello

One might take issue with this statement in the manpage though,

The  functions  beginning  `TRAP'  may alternatively be defined with the trap
builtin:  this may be preferable for some uses, as they are then run  in  the
environment  of  the calling process, rather than in their own function envi‐
ronment.  Apart from the difference in calling procedure and  the  fact  that
the function form appears in lists of functions, the forms

              TRAPNAL() {
               # code
              }

       and

              trap '
               # code
              ' NAL

       are equivalent.


-- 
Mikael Magnusson