password_number
    OpenVMS usage:value
    type:         longword (unsigned)
    access:       read only
    mechanism:    by value
    A numeric value indicating which password to prompt for and what
    action to take on it:
    ValuePrompt for
    0    Primary password and validate it
    1    Secondary password and validate it
    -1   Primary password but do not validate it
    -2   Secondary password but do not validate it
    -3   Arbitrary 32-character value returned to buffer specified in
         buffer
    If the value is -3, you must specify the prompt argument and the
    buffer argument.
 prompt
    OpenVMS usage:character string
    type:         string descriptor
    access:       read only
    mechanism:    by reference
    String that must begin with "cr,lf". If this argument is not
    supplied, the standard prompt is used.
 buffer
    OpenVMS usage:character string
    type:         string descriptor
    access:       modify
    mechanism:    by reference
    Buffer having at least 32 bytes available to store password when
    password_number argument value is -3.