Re: interrupting loops

[P.Stephenson@xxxxxxxxxxxxx]

Just found this old message:

mark%eggman.uucp@xxxxxxxx wrote:
> Richard writes:
> >> prompt% for x in 1 2 3 4 5; do
> >> > echo $x
> >> > sleep 1
> >> > done
> >> If you try to interrupt that loop, the sleep command gets interrupted,
> >> but then the loop continues with the next iteration.  I tried the same
> >> loop on ksh and sh, and both of the popped out of the loop just fine.
> >
> >I'm not able to duplicate this.  What machine type and zsh options
> >are you using?
> It looks like it's triggered by my having a TRAPZERR function defined.

dotrap() was being called although the function itself didn't do
anything because of the error flag.  I've put a test into dotrap(),
but note the comment.  The last part of the comment refers to another
bug I found at the same time which I'll post separately.

*** Src/signals.cerrt	Wed May 31 05:10:36 1995
--- Src/signals.c	Thu Jun  8 19:48:18 1995
***************
*** 681,688 ****
   
      sav = sigtrapped[sig];
      savval = lastval;
!     if (sav == 2)          /* if signal is being ignored, return */
          return;
      sigtrapped[sig] = 2;
      if (sigfuncs[sig]) {
          Lklist args;
--- 681,696 ----
   
      sav = sigtrapped[sig];
      savval = lastval;
!     if (errflag || sav == 2)
          return;
+     /* If signal is being ignored, return.
+      *  
+      *  Also return if errflag is set.  In fact, the code in the
+      *  function will test for this, but this way we keep status flags
+      *  intact without working too hard.  Special cases (e.g. calling
+      *  a trap for SIGINT after the error flag was set) are handled
+      *  by the calling code.  (PWS 1995/06/08).
+      */
      sigtrapped[sig] = 2;
      if (sigfuncs[sig]) {
          Lklist args;

-- 
Peter Stephenson <P.Stephenson@xxxxxxxxxxxxx>  Tel: +44 1792 205678 extn. 4461
WWW:  http://python.swan.ac.uk/~pypeters/      Fax: +44 1792 295324
Department of Physics, University of Wales, Swansea,
Singleton Park, Swansea, SA2 8PP, U.K.