How to get the target of an HTTP redirect with curl
I wanted to check where an HTTP URL redirects using curl.
I came up with the following command:
# Get the URL where "$url" redirects to (or $url, if it doesn't redirect).
#
# Flags:
#
# --head = only fetch the headers, don't download the page
# --location = follow redirections
# --write-out = print the final URL fetched to stdout
# --silent = don't print any progress information
# --show-error = show an error message if curl fails
# --output /dev/null = don't print curl's default output, which would
# be the headers from every URL it fetched
#
curl "$url" \
--head \
--location \
--write-out "%{url_effective}" \
--silent --show-error \
--output /dev/null
If I only want to follow a single redirect, I can add the --max-redirs flag.
As I was writing this command, I had a vague memory of the --write-out flag – it’s one of Daniel Stenberg’s “personal favourites” and I wrote about using it in a TIL in May.