Get URL's redirect target with curl
There is an even easier way
curl -w "%{url_effective}\n" -I -L -s -S $URL -o /dev/null
it would print
http://raspberrypi.stackexchange.com/questions/1508/how-do-i-access-the-distributions-name-on-the-command-line/1521
for URL
http://raspberrypi.stackexchange.com/a/1521/86
Try this:
$ LOCATION=`curl -I http://raspberrypi.stackexchange.com/a/1521/86 | perl -n -e '/^Location: (.*)$/ && print "$1\n"'`
$ echo "$LOCATION"
/questions/1508/how-do-i-access-the-distributions-name-on-the-command-line/1521#1521
Google Redirects
Google redirect URLs are slightly different. They return a Javascript redirect, which could easily be processed, but why not process the original URL and for go curl all together?
$ URL="http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CFAQFjAA&url=http%3A%2F%2Fwww.raspberrypi.org%2F&ei=rv8oUODIIMvKswa4xoHQAg&usg=AFQjCNEBMoebclm0Gk0LCZIStJbF04U1cQ"
$ LOCATION=`echo "$URL" | perl -n -e '/url=([a-zA-Z0-9%\.]*)/ && print "$1\n"'`
$ echo "$LOCATION"
http%3A%2F%2Fwww.raspberrypi.org%2F
$ echo "$LOCATION" | perl -pe 's/%([0-9a-f]{2})/sprintf("%s", pack("H2",$1))/eig'
http://www.raspberrypi.org/
Reference
- For url decode...
curl can be configured to follow redirects and to print variables after completion. So what you ask can be achieved with the following command:
curl -Ls -w %{url_effective} -o /dev/null https://google.com
The man page explains the necessary parameters like that:
-L, --location Follow redirects (H)
-s, --silent Silent mode (don't output anything)
-w, --write-out FORMAT Use output FORMAT after completion
-o, --output FILE Write to FILE instead of stdout