How to curl case-insensitive

It's not curl that decides case-insensitivity at all link "checking" is the server's decision.

(In other words, HTTP clients do not have the opportunity to see the list of all possible URLs and choose a matching one. The only thing an HTTP client can do is give the exact URL to the server and let the server decide how to respond. Some servers are case-insensitive, some are not.)

But if you already know that you need a lowercase 'linux', you can just transform the uname output before giving it to curl, e.g. by piping it through tr A-Z a-z to change all uppercase letters to lowercase:

docker-$(uname -s | tr A-Z a-z)

or by using Bash's ${var,,} expansion to return a lowercase version of $var:

os=$(uname -s); arch=$(uname -m)
docker-${os,,}-${arch}

Finally, since there's only a small set of accepted values, and because the accepted values aren't guaranteed to be "uname but lowercase" in general, you could indirectly assign each possible value (using if or case blocks), for example:

case $(uname -s) in
    Darwin)    docker_os='darwin';;
    Linux)     docker_os='linux';;
    Cygwin)    docker_os='windows';;
    Microsoft) docker_os='windows';;
    *)         echo "Docker is not supported on this OS!" >&2; exit 1;;
esac

^{(Note: The 'windows' examples are completely made up. )}

Solved by user718047 (2,046 )
Aug 02, 2022 at 06:35