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Dont what this sed expression does

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# 1  
Old 12-06-2009
Question Dont what this sed expression does
I am new to unix and have come across the sed expression but not sure what its doing. Can someone please tell me whats happening in the sed command below?

Quote:
abc(){

sed "/debug=\"false\"/{x;N;s/.*/threshold=\"$1\"/;x;G;}" testFile.xml > testFileNew.xml
mv testFileNew.xml testFile.xml
}

abc $1
# 2  
Old 12-07-2009
man sed, please

Code:
      g G    Copy/append hold space to pattern space.

       x      Exchange the contents of the hold and pattern spaces.

      s/regexp/replacement/
              Attempt to match regexp against the pattern space.  If  success-
              ful,   replace  that  portion  matched  with  replacement.   The
              replacement may contain the special character & to refer to that
              portion  of  the  pattern  space  which matched, and the special
              escapes \1 through \9 to refer  to  the  corresponding  matching
              sub-expressions in the regexp.
      n N    Read/append the next line of input into the pattern space.

# 3  
Old 12-08-2009
Break the sed statement
I was wondering if we can break the sed command into two or more sets of command. What I mean is that rather than having everything in one line we can have

sed ...

sed...

sed ..

Can anyone help ?

---------- Post updated at 04:25 PM ---------- Previous update was at 10:17 AM ----------

Can anyone help me with my previous comment ?
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