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Variable in sed

 
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# 1  
Old 12-07-2015
RedHat Variable in sed
First post on this excellent forum.

I have problem using an variable in sed. I've been quoting until my eyes bleeds nowSmilie

I want to match IPV6 addresses and join it with the line that follows.
This works when i use it without an variable.
Code:
cat test.txt | sed -e '/^2001/{N;s/\n//;}'

But when i try to match with an variable that matches al kinds of IPV6 standards. The variable works when i try to grep with it so now problem there.

So how do i quote to make this work?
Code:
cat test.txt | sed -e '/^$IPV6CHECK/{N;s/\n//;}'

Example on text.txt
Code:
2001:0db8:0:1428::2
                  0 111029  522163 0    0     4w6d          3
2001:0db8:0:1429::2
                  0 51162  202540 0    0     3w3d          4
2001:0db8:0:1410::2
                  0 175342  597906 0    0    5d12h          7
2001:0db8:0:1411::2
                  0 53682  243980 0    0    5d12h          7
2001:0db8:0:1448::2
                  0 104945  601349 0    0     5w0d          4

Desired output:
Code:
2001:0db8:0:1428::2                  0 111029  522163 0    0     4w6d          3
2001:0db8:0:1429::2                  0 51162  202540 0    0     3w3d          4
2001:0db8:0:1410::2                  0 175342  597906 0    0    5d12h          7
2001:0db8:0:1411::2                  0 53682  243980 0    0    5d12h          7
2001:0db8:0:1448::2                  0 104945  601349 0    0     5w0d          4

Last edited by Scrutinizer; 12-08-2015 at 05:50 AM.. Reason: Adding code tags; removed spurious font tags
# 2  
Old 12-07-2015
Use double quotes to allow variable expansion.
Also, loose the cat , since it is useless here.
Code:
sed -e "/^$IPV6CHECK/{N;s/\n//;}" test.txt

Best regards
Peasant.
# 3  
Old 12-08-2015
Quote:
Originally Posted by Peasant
Use double quotes to allow variable expansion.
Also, loose the cat , since it is useless here.
Code:
sed -e "/^$IPV6CHECK/{N;s/\n//;}" test.txt

Best regards
Peasant.
Thanks for reply.
If it only had been that easy.
The variable has a complex regex. I think thats the problem. Varible works with grep

Code:
IPV6CHECK="(([0-9a-fA-F]{1,4}:){7,7}[0-9a-fA-F]{1,4}|([0-9a-fA-F]{1,4}:){1,7}:|([0-9a-fA-F]{1,4}:){1,6}:[0-9a-fA-F]{1,4}|([0-9a-fA-F]{1,4}:){1,5}(:[0-9a-fA-F]{1,4}){1,2}|([0-9a-fA-F]{1,4}:){1,4}(:[0-9a-fA-F]{1,4}){1,3}|([0-9a-fA-F]{1,4}:){1,3}(:[0-9a-fA-F]{1,4}){1,4}|([0-9a-fA-F]{1,4}:){1,2}(:[0-9a-fA-F]{1,4}){1,5}|[0-9a-fA-F]{1,4}:((:[0-9a-fA-F]{1,4}){1,6})|:((:[0-9a-fA-F]{1,4}){1,7}|:)|fe80:(:[0-9a-fA-F]{0,4}){0,4}%[0-9a-zA-Z]{1,}|::(ffff(:0{1,4}){0,1}:){0,1}((25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])\.){3,3}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])|([0-9a-fA-F]{1,4}:){1,4}:((25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])\.){3,3}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9]))"
sed -e "/^$IPV6CHECK/{N;s/\n//;}" test.txt

Smilie
# 4  
Old 12-08-2015
Peasant is correct, you need the double quotes. In addition, IPV6CHECK contains a regular expression that is an ERE (extended regular expression), so it will work with grep -E. sed uses basic regular expressions (BRE) so it will not work there.

You can use GNU sed with the -r option or BSD sed with the -E option, that can handle ERE:
Code:
$ gsed -r "/^$IPV6CHECK/{N;s/\n//;}" infile
2001:0db8:0:1428::2                  0 111029  522163 0    0     4w6d          3
2001:0db8:0:1429::2                  0 51162  202540 0    0     3w3d          4
2001:0db8:0:1410::2                  0 175342  597906 0    0    5d12h          7
2001:0db8:0:1411::2                  0 53682  243980 0    0    5d12h          7
2001:0db8:0:1448::2                  0 104945  601349 0    0     5w0d          4

# 5  
Old 12-08-2015
Quote:
Originally Posted by Scrutinizer
Peasant is correct, you need the double quotes. In addition, IPV6CHECK contains a regular expression that is an ERE (extended regular expression), so it will work with grep -E. sed uses basic regular expressions (BRE) so it will not work there.

You can use GNU sed with the -r option or BSD sed with the -E option, that can handle ERE:
Code:
$ gsed -r "/^$IPV6CHECK/{N;s/\n//;}" infile
2001:0db8:0:1428::2                  0 111029  522163 0    0     4w6d          3
2001:0db8:0:1429::2                  0 51162  202540 0    0     3w3d          4
2001:0db8:0:1410::2                  0 175342  597906 0    0    5d12h          7
2001:0db8:0:1411::2                  0 53682  243980 0    0    5d12h          7
2001:0db8:0:1448::2                  0 104945  601349 0    0     5w0d          4

Thanks
I cant make it work on Redhat with sed -e. gsed is not available. It seams it wont match.

This is my test file.
Code:
#!/bin/bash
IPV6CHECK="(([0-9a-fA-F]{1,4}:){7,7}[0-9a-fA-F]{1,4}|([0-9a-fA-F]{1,4}:){1,7}:|([0-9a-fA-F]{1,4}:){1,6}:[0-9a-fA-F]{1,4}|([0-9a-fA-F]{1,4}:){1,5}(:[0-9a-fA-F]{1,4}){1,2}|([0-9a-fA-F]{1,4}:){1,4}(:[0-9a-fA-F]{1,4}){1,3}|([0-9a-fA-F]{1,4}:){1,3}(:[0-9a-fA-F]{1,4}){1,4}|([0-9a-fA-F]{1,4}:){1,2}(:[0-9a-fA-F]{1,4}){1,5}|[0-9a-fA-F]{1,4}:((:[0-9a-fA-F]{1,4}){1,6})|:((:[0-9a-fA-F]{1,4}){1,7}|:)|fe80:(:[0-9a-fA-F]{0,4}){0,4}%[0-9a-zA-Z]{1,}|::(ffff(:0{1,4}){0,1}:){0,1}((25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])\.){3,3}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])|([0-9a-fA-F]{1,4}:){1,4}:((25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])\.){3,3}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9]))"
sed -e "/^$IPV6CHECK/{N;s/\n//;}" test.txt

I manage to make it work. But not in an pretty way Smilie
Code:
egrep -A1 "^$IPV6CHECK" test.sh | sed -e "s/ /_/g" | xargs -n 2 | awk '{ print $1,$2 }' | sed -e "s/_/ /g"

# 6  
Old 12-08-2015
Yes GNU sed is the default sed on Redhat Linux, so it is called sed and it should work there, but you need to use sed -r, not sed -e.

On my system it is called gsed that is why my example uses gsed.
This User Gave Thanks to Scrutinizer For This Post:
OXYD
# 7  
Old 12-08-2015
Why is your IPV6CHECK that difficult? Wouldn't IPV6CHECK="([[:xdigit:]]*:){5}[[:xdigit:]]*" suffice?
 
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