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Re: Broken backquote behavior in bash?



 John Abreau wrote: 
> When I try to use backquotes on the command line on this server, I get 
> no output. 
>     $ echo `echo bar` 
> 
> 
> Other symptoms include pipes not working ("ls | more" exits immediately 
> with no output), backgrounding fails ("foo &" returns "[1]+  Broken 
> pipe  foo"). 

So basically anything that requires launching a subshell fails. I bet this: 

$ echo foo; (echo bar) 
foo 
bar 

will probably output only "foo". 

I'd expect it to produce an error message if it was having problems 
launching the subshell, but I suppose that might not happen if the shell 
it is trying to execute is something like /bin/false. 

Check the environment variables for anything odd, and run an instance of 
the shell with strace, logging to a file, and try starting a subshell. 


> ...specifically affects users that are defined in LDAP... 

What does the system think their login shell should be? (That alone 
wouldn't explain this, as the initial login would fail too, unless the 
login process is hard coded to use bash.) 

Sounds like it could alternatively be an SELinux problem, though I'd 
expect that to produce an error message. 

  -Tom 

-- 
Tom Metro 
Venture Logic, Newton, MA, USA 
"Enterprise solutions through open source." 
Professional Profile: http://tmetro.venturelogic.com/

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