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explanation of test function

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# 1  
Old 07-06-2011
explanation of test function
I have found a code some where, which looks like
Code:
if (test $value)
then
<do something>
fi

I am not understanding what is test doing here. I have seen test with !,-eq, -e etc.
But, the above appears to be a new one to me.
Can anyone please expalin me.
# 2  
Old 07-06-2011
man test

test

Moderator's Comments:
Mod Comment Simply posting a link to a man page is discouraged here. Posting a link to aman page is fine, but please add more value to the post. Thanks.
# 3  
Old 07-06-2011
I have written sort test/if some years ago.
# 4  
Old 07-06-2011
with no operator it is "True if string is not empty."
# 5  
Old 07-06-2011
Code:
if test $value   # no need to create subprocess 
then 
    doSomething
fi

Code:
if  [ $value ]
then
   doSomething
fi

If value is set, then test return exit code 0 = true

Code:
# about same, more generic,  documentation is better
if  [ "$value" != "" ]
then
   doSomething
fi

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