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Variable in bash help

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# 1  
Old 11-28-2013
Variable in bash help
Code:
 #aa=xxxx
 #zz="cc $aa"
 #aa=gggg
 #echo $zz

out put is 
 cc xxxx

if I want to get 
 cc gggg

how should I do, I don't want to write zz="c $aa " after aa=gggg

# 2  
Old 11-28-2013
Quote:
I don't want to write zz="c $aa " after aa=gggg
Why?
# 3  
Old 11-28-2013
Quote:
Originally Posted by yanglei_fage
Code:
 #aa=xxxx
 #zz="cc $aa"
 #aa=gggg
 #echo $zz

out put is 
 cc xxxx

if I want to get 
 cc gggg

how should I do, I don't want to write zz="c $aa " after aa=gggg

First:
Code:
zz="cc $aa"

will not produce:
Code:
 cc xxxx

because there is a leading space in the output.

Second: It is good that you don't want to use:
Code:
zz="c $aa "

because the output you want to get includes a leading space, "cc" instead of "c", and no trailing space. So, what you need is:
Code:
zz=" cc $aa"

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