How can I script file upload to an owncloud shared link folder?
curl -u token:password -T filename "https://your.owncloud.server/public.php/webdav/filename"The token is the string at the end of the shared link (e.g. abcdefghijk0123 in https://your.owncloud.server/index.php/s/abcdefghijk0123). If you don't use a password to protect the link you can leave the field in the command blank.
You could try to create an app password on https://your-owncloud-server/settings/personal#apppasswords, that way you wouldn't need an other user account.
Edit: only works on Nextcloud