The .* is greedy, that means it consumes as many characters as possible - while the other conditions are still met.
If there are two .* then the leftmost is most greedy.
Last edited by MadeInGermany; 05-06-2016 at 10:32 AM..
These 2 Users Gave Thanks to MadeInGermany For This Post:
Greedy means earlier parts of the regex "win", they will match as far as they can. They'll only ever give it up when the rest of the expression fails to match. So the first .* matches all the way to the end, stealing the entire expression if it can get away with it, and backtracking when it can't.
Code:
.*\(-.*-).*
Code:
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continueDate-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Date-range on 5th May is between -010516 and 050516- please continue
Last edited by Corona688; 05-06-2016 at 02:23 PM..
These 2 Users Gave Thanks to Corona688 For This Post:
Hi Don, thankyou very much for your time in explaining that to me.
However, after doing a bit of testing im still slightly confused and would like to understand :
"The -.*- between the parens in that RE will match the 1st - on the line ( - in the RE), everything after the 1st - unto but not including the
last - on the line ( .* in the RE), and the last - on the line ( - in the RE)."
Code:
echo "Date-range on 5th May is between -010516 and 050516- please continue "| sed 's/.*\(-.*-\).*/\1/'
output
-010516 and 050516-
Why is this not -range on 5th May is between -010516 and 050516- ?
Code:
echo "Date range on 5th May is between -010516 and 050516- please-continue "| sed 's/.*\(-.*-\).*/\1/'
output
- please-
Why is this not -010516 and 050516- please- ?
For the second statement:
"The RE between parentheses in this sed substitute command ( -[^-]*- ) matches the 1st - on the line ( - in the RE),
the longest string of characters available that does not include a - ( [^-]* in the RE), and the 2nd - on the line ( - in the RE)."
Code:
echo "Date-range on 5th May is between -010516 and 050516- please continue "| sed 's/.*\(-[^-]*-\).*/\1/'
output
-010516 and 050516-
Why is this not -range on 5th May is between - ?
Code:
echo "Date range on 5th May is between -010516 and 050516- please-continue "| sed 's/.*\(-[^-]*-\).*/\1/'
output
- please-
Why is this not -010516 and 050516- ?
Thanks again
I sincerely apologize. I haven't been getting enough sleep lately.
It looks like Corona688 and MadeInGermany have mostly cleaned up my mess. I sincerely thank both of them for correcting my earlier misinformation.
If you want to print everything between the 1st and last dashes on a line (including the dashes), you need something like:
Code:
echo "Date-range on 5th May is between -010516 and 050516- please continue "| sed 's/[^-]*\(-.*-\).*/\1/'
producing the output:
Code:
-range on 5th May is between -010516 and 050516-
If you want to print everything between the 1st and last dashes on a line (not printing the 1st and last dashes), you need something like:
Code:
echo "Date-range on 5th May is between -010516 and 050516- please continue "| sed 's/[^-]*-\(.*\)-.*/\1/'
producing the output:
Code:
range on 5th May is between -010516 and 050516
If you want to print everything between the 1st two dashes on a line (printing those dashes), you need something like:
Code:
echo "Date-range on 5th May is between -010516 and 050516- please continue "| sed 's/[^-]*\(-[^-]*-\).*/\1/'
producing the output:
Code:
-range on 5th May is between -
And, if you want to print everything between the 1st two dashes on a line (not printing those dashes), you need something like:
Code:
echo "Date-range on 5th May is between -010516 and 050516- please continue "| sed 's/[^-]*-\([^-]*\)-.*/\1/'
producing the output:
Code:
range on 5th May is between
Note that in all of these substitution BREs, the expression before the parenthesized expression we will print starts with [^-]* which will greedily gobble up as many non-dash characters as it can find (but not any dashes).
This User Gave Thanks to Don Cragun For This Post:
i have a large file where i want to look for any record that is is larger or smaller than 21 and if it is the case i want to report and break SED .. how can i achieve it ?
i dont want sed to scan the complete file after one non match is found. (4 Replies)
Hi, i have file file.txt with data like:
START
03:11:30 a
03:11:40 b
END
START
03:13:30 eee
03:13:35 fff
END
jjjjjjjjjjjjjjjjjjjjj
START
03:14:30 eee
03:15:30 fff
END
ggggggggggg
iiiiiiiiiiiiiiiiiiiiiiiii
I want the below output
START (13 Replies)
I am using following sed rule to delete 2 lines after a pattern match inclusive.
# cat /tmp/temp.txt
dns.com
11
22
mydns.com
11
22
dns.com.au
11
22
LAST LINE
# cat /tmp/temp.txt | sed -e '/dns.com/,+2d'
LAST LINE
I just need to remove lines below dns.com only and NOT below... (5 Replies)
I would like replace all the rows in a file if a row has an exact match to number say 21 in a tab delimited file. I want to delete the row only if it has 21 any of the rows but it should not delecte the row that has 542178 or 563421.
I tried this
sed '/\<21\>/d' ./inputfile > output.txt
... (7 Replies)
Hi Guys
So far I have got this to work:
set x = temp1:temp2:temp3
echo $x | sed 's/.*:\(.*\).*/\1/'
Answer:
temp3
But I want answer as temp2:temp3, that is everything after the first ":" is found. If anybody can help with a bit of description that will be great.
Thanks in Advance (1 Reply)
Hi,
I would like to use SED to do the following string replacement:
asd1abc to www1cda
asd2abc to www2cda
...
asd9abc to www9cda
I can use 'asd.abc' to find the orignal string, however I don't know how to generate the target string. Any suggestion?
Thanks,
... (2 Replies)
Hi:
it seems very strange.
there is a file with multiple lines. After I squeezed out the consecutive blank lines (and some other text processing), somehow the
sed '/\n/! d' file
can not generate any output, as if it can't find any line with newline.
the file is has many lines, so... (9 Replies)
Please help!
Input pattern, where ... could be any number of lines
struct A {
Blah1
Blah2
Blah3
...
} B;
output pattern
struct AB {
Blah1
Blah2
Blah3
...
};
I need help in extracting everything between { and }
if it would have been on a single line { \(.*\)} should have worked. (15 Replies)
I have a text file that has links in it.
I can write a match for sed to replace the link with anything.
For example:
http://www.google.com
becomes
XxX
But what I'm after is not to replace the link with something but to remove everything else and just leave the link. I want a... (5 Replies)
05-06-2016
