[adding zsh list] On 07/07/2011 08:46 AM, Herbert Xu wrote: > On Thu, Jul 07, 2011 at 07:26:50AM -0600, Eric Blake wrote: >> >> zsh rejected the continue statement (no containing loop within the >> current scoping of the dot script), and as a result also aborted the >> overall dot script - but in doing so, it properly emitted an error message. > > dash does not warn in this case because it never prints a warning > on continue anywhere. > > This behaviour (not warning) is consistent with that of ksh. Interesting! And bash indeed behaves differently: in POSIX mode it is silent, while in bash mode it issues a warning but does not affect exit status - in line with the fact that in POSIX mode, bash obeys the rule that if an application is diagnosing something to stderr, then the exit status should be non-zero (and warnings don't affect exit status, hence warnings should not be issued in POSIX mode). Zsh is treating it as a syntax error, which is different from all the other shells: $ bash -c 'continue; echo $?' bash: line 0: continue: only meaningful in a `for', `while', or `until' loop 0 $ bash --posix -c 'continue; echo $?' 0 $ dash -c 'continue; echo $?' 0 $ ksh -c 'continue; echo $?' 0 $ zsh -c 'emulate sh; continue; echo $?' zsh:continue:1: not in while, until, select, or repeat loop $ echo $? 1 POSIX states "If n is greater than the number of enclosing loops, the outermost enclosing loop shall be exited." But this is admittedly silent on the behavior when there is no outermost enclosing loop, so I'm not sure whether zsh treating this as a syntax error is appropriate. Meanwhile, I still have to wonder about dash behavior - if dash is _not_ treating continue as a syntax error, then why is it aborting the dot script? Compare: $ dash -c 'continue echo $?' 0 $ dash -c 'printf "continue\\necho 0.\$?\\n" > f; for i in 1; do . ./f; echo 1.$?; done; echo 2.$?' 1.0 2.0 In isolation, execution after an un-nested continue resumed with the next statement, but in the dot script, execution after the "un-nested" continue (at least, from the dot script perspective) aborted the dot script, but without affecting exit status. -- Eric Blake eblake@xxxxxxxxxx +1-801-349-2682 Libvirt virtualization library http://libvirt.org
Attachment:
signature.asc
Description: OpenPGP digital signature