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Basic sed doubts

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# 1  
Old 09-26-2013
Basic sed doubts
Hi,

I am a newbie to sed environment.
Have been trying to understand some basics of the language,

I am required to replace the occurence of a text string with 0...the command that has been told to me is this
Code:
"s/^\s<=k/0/" -e

Can some one please explain me how to
break the command for understanding. AS in

I do know that s is used for substitution and ^ is used to
indicate the begining of the string or something.
Can someone please tell what is the utility of \s.

TIA
Last edited by Scott; 09-26-2013 at 07:38 AM.. Reason: Fixed code tags
# 2  
Old 09-26-2013
  • ^ ... begin of line, as you already pointed out
  • \s ... whitespace character (blank, tab)
  • <=k ... a string literal
This User Gave Thanks to hergp For This Post:
seddoubt
# 3  
Old 09-26-2013
sorry to bug u again

Code:
s/,[ ]*?[ ]*,/, ,/g

what does this do ?

Smilie
Last edited by Scott; 09-26-2013 at 07:39 AM.. Reason: Fixed code tags
# 4  
Old 09-26-2013
Substitute the sequence
  • , ... one comma
  • [ ]* ... zero or more blanks
  • ? ... a question mark
  • [ ]* ... zero or more blanks
  • , ... one comma
with
  • , , ... the string comma-blank-comma
and g ... do it for all matches in a line, not only the first
These 2 Users Gave Thanks to hergp For This Post:
Ramesh Rajagopa seddoubt
# 5  
Old 09-27-2013
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