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Re: Broken backquote behavior in bash?



 Just one comment, the preferred Bash construct is to use $() rather 
than backquotes. 
$(/usr/bin/id -u) 

Try changing to: 
if [ $(/usr/bin/id -u) = "0 "] 
if [$(/usr/bin/id -u) -eq 0 ] 

Note that the -eq is for numeric comparisons. 

On Thu, 24 Jul 2008 10:50:34 -0400 
"John Abreau" <[hidden email]> wrote: 

> I've got a server that's been giving strange errors lately. Most 
> noticeably, when I login, 
> I get several errors of the form 
> 
>     -bash: [: =: unary operator expected 
> 
> I've traced these to files under /etc/profile.d, and on further 
> testing I find that the 
> offending lines are using backquotes, e.g. 
> 
>         if [ `/usr/bin/id -u` = 0 ] ; then 
> 
> When I try to use backquotes on the command line on this server, I get 
> no output. 
> Even stranger, if I have a suspended vi job, then running something in 
> backquotes 
> terminates the vi process: 
> 
>     $ vi foo 
>     ^Z 
>     [1]+  Stopped                 nvi foo 
>     $ echo `echo bar` 
> 
>     [1]+  Terminated              nvi foo 
> 
> If I do this on my other systems, I get 
> 
>     $ echo `echo bar` 
>     bar 
> 
> and the vi job does not terminate. 
> 
> I've tried googling for these symptoms, but so far I haven't found a match. 
> Has anyone else run across this odd behavior? What could be causing it? 
> 
> 
> 
> -- 
> John Abreau / Executive Director, Boston Linux &amp; Unix 
> GnuPG KeyID: 0xD5C7B5D9 / Email: [hidden email] 
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> _______________________________________________ 
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