zsh can causes ps to generate error message
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
procps (Ubuntu) |
Fix Released
|
Medium
|
Unassigned |
Bug Description
(ps|grep foo;echo)
Signal 18 (CONT) caught by ps (procps-ng version 3.3.3).
ps:display.c:59: please report this bug
(ps;echo) # works
(ps|grep foo) # works
(ps|grep foo;echo) # fails
This behaviour seems to be caused by zsh since it is not observable using bash. Note too that this bug cannot be recreated on precise.
zsh configuration is stock "system configuration" (run zsh for first time and select option (2) - system defaults).
ProblemType: Bug
DistroRelease: Ubuntu 12.10
Package: zsh 5.0.0-2ubuntu1
ProcVersionSign
Uname: Linux 3.5.0-15-generic i686
ApportVersion: 2.5.2-0ubuntu4
Architecture: i386
Date: Mon Sep 24 16:01:37 2012
InstallationMedia: Ubuntu 12.10 "Quantal Quetzal" - Alpha i386 (20120530)
ProcEnviron:
LANGUAGE=en_GB:en
TERM=xterm
PATH=(custom, no user)
LANG=en_GB.UTF-8
SHELL=/bin/zsh
SourcePackage: zsh
UpgradeStatus: No upgrade log present (probably fresh install)
Changed in procps (Ubuntu): | |
status: | New → Confirmed |
importance: | Undecided → Medium |
The output "ps:display.c:59: please report this bug" is from procps-ng, so I'd suspect it's rather an issue in procps-ng than in zsh.
The difference to bash is possible caused by differences about when subshells are spawned and when not -- an area where the POSIX specification is ambiguous and hence different behaviour is to be expected.
I can also reproduce this issue with zsh from Debian Experimental (on which Quantal's zsh package is based upon) and with zsh in Debian Unstable and Testing (on which Precise's zsh package is based upon). In those case procps 1:3.3.3-2 where used. But Precise has 1:3.2.8-11ubuntu6, so I guess the difference is rather the procps than the zsh version. Reassigning.