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Old 03-07-2006, 02:54 PM   #1
true_atlantis
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variable question


in the following there is a 0 outputted from 'z=ls | wc -w' and i first thought that z would equal 'ls | wc-w' but was confused about the 0, then i thought that the first command z=ls was being piped to wc -w, but then when echoing z i get nothing. my question is what is happening when 'z=ls | wc -w' is run, and why is there a 0 outputted?




atlantis@linux:~> echo $z

atlantis@linux:~> z=ls | wc -w
0
atlantis@linux:~> echo $z

atlantis@linux:~>
 
Old 03-07-2006, 02:55 PM   #2
pljvaldez
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Try using back quotes:
Code:
z=`ls | wc -w`
 
Old 03-07-2006, 03:01 PM   #3
true_atlantis
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yeah, i understand what was wrong. but im just trying to figure out whats going on to output the 0
 
Old 03-07-2006, 03:20 PM   #4
spooon
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the command "z=ls" assigns "ls" to "z" but doesn't output anything, so when you count the words, it's 0
 
Old 03-07-2006, 08:25 PM   #5
true_atlantis
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if it assigns ls to z then why when echoing $z does it not output ls?
 
Old 03-08-2006, 03:48 AM   #6
muha
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because this does not assign ls to z:
Code:
z=ls | wc -w
I guess the space breaks up the 'assigning to a variable' since this does not assign anything to z:
Code:
z=word word
whereas these do assign ls to z:
Code:
z=ls
z=ls; wc -w <somefile>
 
  


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