NE_SET_SERVER_AUTH(3)         neon API reference         NE_SET_SERVER_AUTH(3)

       ne_set_server_auth, ne_set_proxy_auth, ne_forget_auth - register
       authentication callbacks

       #include <ne_auth.h>

       typedef int (*ne_auth_creds)(void *userdata, const char *realm,
                                    int attempt, char *username,
                                    char *password);

       void ne_set_server_auth(ne_session *session, ne_auth_creds callback,
                               void *userdata);

       void ne_set_proxy_auth(ne_session *session, ne_auth_creds callback,
                              void *userdata);

       void ne_forget_auth(ne_session *session);

       The ne_auth_creds function type defines a callback which is invoked
       when a server or proxy server requires user authentication for a
       particular request. The realm string is supplied by the server.  The
       attempt is a counter giving the number of times the request has been
       retried with different authentication credentials. The first time the
       callback is invoked for a particular request, attempt will be zero.

       To retry the request using new authentication credentials, the callback
       should return zero, and the username and password buffers must contain
       NUL-terminated strings. The NE_ABUFSIZ constant gives the size of these

           If you only wish to allow the user one attempt to enter
           credentials, use the value of the attempt parameter as the return
           value of the callback.

       To abort the request, the callback should return a non-zero value; in
       which case the contents of the username and password buffers are

       The ne_forget_auth function can be used to discard the cached
       authentication credentials.

           /* Function which prompts for a line of user input: */
           extern char *prompt_for(const char *prompt);

           static int
           my_auth(void *userdata, const char *realm, int attempts,
                   char *username, char *password)
              strncpy(username, prompt_for("Username: "), NE_ABUFSIZ);
              strncpy(password, prompt_for("Password: "), NE_ABUFSIZ);
              return attempts;

           int main(...)
              ne_session *sess = ne_session_create(...);

              ne_set_server_auth(sess, my_auth, NULL);

              /* ... */

       Joe Orton <>

neon 0.29.3                     11 January 2010          NE_SET_SERVER_AUTH(3)