sed with read input

[johnho]

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

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

[Steven E. Protter]

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

[Mel Burslan]

have you tried:

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

yet ?

[James R. Ferguson]

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...

[johnho]

#!/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

[James R. Ferguson]

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...

[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 carriage return in its end. (such as \n or \r)

[Dennis Handly]

>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