topic Re: sed with read input in Operating System - HP-UX

sed with read input

johnho — Thu, 23 Jul 2009 13:09:29 GMT

problem with shell scripting:
The sed command doesn't work.. Do you know what is the correct syntax of sed command?
I want to change the IP-address of the APN.

Many thanks.

John

#!/bin/sh

printf "Which APN you want to migrate? "
read APN
printf "\n\n"
printf "You want to migrate this APN: $APN"
printf "\n\n"
printf "Current IP of this APN: $APN"
printf "\n\n"
cat gprs.zone | grep "$APN"
printf "\n\n"
printf "\n\n"
sed '/$APN/s/10.10.10.12/10.10.10.225/g' gprs.zone > gprs.zone.new
sed '/$APN/s/10.10.10.40/10.10.10.229/g' gprs.zone > gprs.zone.new
printf "result"
printf "\n\n"
cat gprs.zone.new | grep "$APN"
exit

Printout of the shell script.
***********************************************

Which APN you want to migrate? test.com

You want to migrate this APN: test.com

Current IP of this APN: test.com

test.com IN A 10.10.10.40
test.com IN A 10.10.10.12

result

test.com IN A 10.10.10.40
test.com IN A 10.10.10.12

***********************************************

Re: sed with read input

Steven E. Protter — Thu, 23 Jul 2009 13:15:42 GMT

Shalom,

Sed examples.

$commandline = "sed s/juf.org/juf.net/g ${filetoback} > $filetoback.bck";

system("${commandline}");
$commandline = "cp ${filetoback}.bck ${filetoback}";
system("${commandline}");

This is pulled from a perl script that goes to the command shell to do some sed conversion.

Pretend the perl part isn't around.

the cp command copies the output of the sed command over the original data file.

SEP

Re: sed with read input

Mel Burslan — Thu, 23 Jul 2009 13:17:07 GMT

have you tried:

cat gprs.zone | sed '/$APN/s/10.10.10.12/10.10.10.225/g' > gprs.zone.new

yet ?

Re: sed with read input

James R. Ferguson — Thu, 23 Jul 2009 13:38:46 GMT

Hi:

Using:

# sed '/$APN/s/10.10.10.40/10.10.10.229/g'

...with the single quotes is not going to allow interpolation of your APN variable. Instead use:

# sed "/$APN/s/10.10.10.40/10.10.10.229/g"

Regards!

...JRF...

Re: sed with read input

johnho — Thu, 23 Jul 2009 14:05:21 GMT

#!/bin/sh

printf "Which APN you want to migrate? "
read APN
printf "\n\n"
printf "You want to migrate this APN: $APN"
printf "\n\n"
printf "Current IP of this APN: $APN"
printf "\n\n"
cat gprs.zone | grep "$APN"
printf "\n\n"
printf "\n\n"

sed "/$APN/s/10.10.10.12/10.10.10.225/g" gprs.zone > gprs.zone.new
sed "/$APN/s/10.10.10.40/10.10.10.229/g" gprs.zone > gprs.zone.new

printf "result"
printf "\n\n"
cat gprs.zone.new | grep "$APN"
exit

Result of the script:

Which APN you want to migrate? test.com

You want to migrate this APN: test.com

Current IP of this APN: test.com

test.com IN A 10.10.10.40
test.com IN A 10.10.10.12

result

test.com IN A 10.10.10.229
test.com IN A 10.10.10.12

It is better now but still not 100%.
Problem now is: the second IP-address is not changed... do I need to do for or while loop?

Best regards,

John

Re: sed with read input

James R. Ferguson — Thu, 23 Jul 2009 14:16:55 GMT

Hi (again) John:

> Problem now is: the second IP-address is not changed... do I need to do for or while loop?

Yes, you overwrote your output when you did the second substitution!

# sed -e "/$APN/s/10.10.10.12/10.10.10.225/g" -e "/$APN/s/10.10.10.40/10.10.10.229/g" gprs.zone > gprs.zone.new

...will fix your problem.

Regards!

...JRF...

Re: sed with read input

Tingli — Thu, 23 Jul 2009 14:34:55 GMT

The funny thing is that sed won't work for the last line in a file, as the last line doesn't have a carriage return in its end. (such as \n or \r)

Re: sed with read input

Dennis Handly — Fri, 24 Jul 2009 08:56:30 GMT

>sed '/$APN/s/10.10.10.12/10.10.10.225/g'

To be pedantic, you should quote each ".":
sed /$APN/s/'10\.10\.10\.12/10.10.10.225/g'

>Tingli: The funny thing is that sed won't work for the last line in a file, as the last line doesn't have a newline in its end.

That's way it is suppose to work. sed only works on text files and lines must be terminated by a newline.
http://docs.hp.com/en/B2355-60130/glossary.9.html#d0e1257203