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Something interesting of this command line

 
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# 1  
Old 02-23-2008
Something interesting of this command line
TEST is assigned as empty.

>TEST=
>if [ "$TEST"="ww" ] ; then echo not empty ; else echo empty ; fi

But it prints Not Empty. What's wrong here? Thanks.
# 2  
Old 02-23-2008
You have to put spaces around the equal sign:

Code:
if [ "$TEST" = "ww" ] ; then echo not empty ; else echo empty ; fi

# 3  
Old 02-23-2008
already answered
# 4  
Old 02-23-2008
Thanks, what is the difference between:
if [ "$TEST" = "ww" ]
and
if [ "$TEST"="ww" ]

?
# 5  
Old 02-23-2008
I guess you are making assignment instead of compare it. Assignment is successful so 'if' thinks that condition was true.
# 6  
Old 02-24-2008
Really? Assigned "ww" to an empty string "" ? (Remember shell replaces $TEST with the empty string first)

Quote:
Originally Posted by SebaM6
I guess you are making assignment instead of compare it. Assignment is successful so 'if' thinks that condition was true.
# 7  
Old 02-24-2008
Quote:
Originally Posted by meili100
Thanks, what is the difference between:
if [ "$TEST" = "ww" ]
and
if [ "$TEST"="ww" ]

?
The second is illegal syntax.
 
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