ports/180178: shells/zsh: hangs upon '>(command)' redirections

[Daniel Shahaf]

>Number:         180178
>Category:       ports
>Synopsis:       shells/zsh: hangs upon '>(command)' redirections
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-ports-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Jul 01 19:30:00 UTC 2013
>Closed-Date:
>Last-Modified:
>Originator:     Daniel Shahaf
>Release:        9.1-RELEASE-p3
>Organization:
elego Software Solutions GmbH
>Environment:
FreeBSD loki.apache.org 9.1-RELEASE-p3 FreeBSD 9.1-RELEASE-p3 #0 r250118: Tue Apr 30 22:06:26 UTC 2013     root at loki.apache.org:/usr/obj/usr/src/sys/ASF  amd64

Using zsh 5.0.2 from ports:

% echo $ZSH_VERSION
5.0.2
>Description:
zsh hangs when commands involving '>(command)' are involved:

[[[
% ssh loki.apache.org 'zsh -fc "echo >(wc -l)"' 
/tmp/zshJHGd5f

]]]

It responds to ^C and ^Z but not to ^D or ^\.

Using ':' or 'true' inside the parentheses yields the same behaviour.
>How-To-Repeat:
zsh -fc "echo >(:)"

OR

zsh -fc ">(:)"

>Fix:
The problem does not appear on either OpenBSD or Linux:

% ssh openbsdbox 'zsh -fc "echo >(true)"' 
/dev/fd/12
% ssh linuxbox 'zsh -fc "echo >(true)"'             
/proc/self/fd/12


>Release-Note:
>Audit-Trail:
>Unformatted: