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Function: ZXCheckUser( <path>, <username>, <password> )

Description:
This function will check whether the given username and password are valid.
<path>     -- Path to ZXMail installation (maybe not required)
<username> -- String of the user ID
<password> -- String of the password

Return values:
0 "User ok."
1 "Error 1. Wrong Number of Arguments."
2 "Error 2. User or password not ok."
3 "Error 3. Other error."

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Function: ZXListUsers( <path>, <stem> )

Description:
<path> -- Path to ZXMail installation (maybe not required)
<stem> -- A stem variable holding all the usernames. username.0 holds
          the number of users.

This function will return a list of usernames.

Return values:
0 "Users listed ok."
1 "Error 1. Wrong Number of Arguments."
2 "Error 2. User list not available."
3 "Error 3. Other error."

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Function: HUserInfo( <path>, <username>, <stem>)

Description:
<path>     -- Path to ZXMail installation (maybe not required)
<username> -- String of the user ID
<stem>     -- A stem variable holding all the user information.

This function will return the user information into the
specified stem variable.

The stem has the format of:

stem.!username = User ID
stem.!realname = Users real name
<others may be added here>

Return values:
0 "Users listed ok."
1 "Error 1. Wrong Number of Arguments."
2 "Error 2. User info not available."
3 "Error 3. Other error."
