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Command substitution within an echo


 
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# 1  
Old 07-23-2009
Command substitution within an echo

I'm trying to get this to work and I'm not really sure how to do it.

Code:
echo $x | awk '{print $NF}' MODIFIED

The output I'm trying to get should look like:

dir1 MODIFIED

Where dir1 will be the result of:

Code:
$x |awk '{print $NF}'

I'm sure there's something I'm supposed to put around that part of it, but I'm new at this and nothing I've tried so far has worked.
# 2  
Old 07-23-2009
Hi.

What is the value of $x that you are trying to execute in your second command?

Code:
$x |awk '{print $NF}

The first part
Code:
echo $x | awk '{print $NF}' MODIFIED

is actually saying that awk reads from stdin (the echo) and from the file called MODIFIED.

You can change this to
Code:
echo $x | awk '{print $NF, "MODIFIED"}'

But without know the meaning of x, it's not clear how you get the value "dir1".
# 3  
Old 07-23-2009
The value of $x is a long line where dir1 is the last word in that line. So I was just trying to pull the last word from that line and add the word MODIFIED to it. Like I said, I'm still kind of new at this and don't really fully understand how awk works. The example you gave is exactly what I was looking for. I appreciate your explanation of why it wasn't working as well. That makes sense and it's nice to know the why instead of just the how.
# 4  
Old 07-23-2009
Hi.

In that case

Code:
echo $x | awk '{print $NF, "MODIFIED"}'

Should do it.
 

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