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Replace a whole line with "#"

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Top Forums Shell Programming and Scripting Replace a whole line with "#"
# 8  
Old 04-28-2013
Actually, I must have been yawning too Smilie, because according to:

Quote:
*+?{
The <asterisk>, <plus-sign>, <question-mark>, and <left-brace> shall be special except when used in a bracket expression (see RE Bracket Expression). Any of the following uses produce undefined results:

If these characters appear first in an ERE, or immediately following a <vertical-line>, <circumflex>, or <left-parenthesis>
ERE Special Characters

So it should be:
Code:
/^\?\?\?/


--edit---
Interestingly with the repeated operators something else seems to be happening:

Code:
$ printf "?\n??\n???\n\naaaaaaa\n" | awk '/^???/'
?
??
???

aaaaaaa


Code:
$ printf "?\n??\n???\n\naaaaaaa\n" | awk '/^z??/'
?
??
???

aaaaaaa

Last edited by Scrutinizer; 04-28-2013 at 03:18 PM..
This User Gave Thanks to Scrutinizer For This Post:
Don Cragun
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