will prompt for a password. Denis Bredelet pointed out!
Specify user and password to use for server authentication. Overrides
\fI-n/--netrc\fP and \fI--netrc-optional\fP.
+If you just give the user name (without entering a colon) curl will prompt for
+a password.
+
If you use an SSPI-enabled curl binary and do NTLM authentication, you can
force curl to pick up the user name and password from your environment by
simply specifying a single colon with this option: "-u :".