Logging into the Qlik Enterprise Manager console prompts for a username and password. The login is generally in the format of domain_name\username. These credentials can be used for curl to obtain a sessionid to run API commands from curl.
You can authenticate either using domain\username or basic authentication using a base64 encoded string of the username and password.
Username and Password:
Open a command prompt
Run the following command, where DOMAIN_NAME\USER is the username you want to authenticate with and <your URL> the hostname.