uid

    The user ID (UID) for which the attributes are to be read.

 pwd

    The location where the retrieved passwd structure is to be
    placed.

 buffer

    A working buffer for the result argument that is able to hold the
    entry in the passwd structure. Storage referenced by the passwd
    structure is allocated from the memory provided with the buffer
    argument, which is bufsize characters in size.

 bufsize

    The length of the character array that buffer points to.

 result

    Upon successful return, result is set to pwd. Upon unsuccessful
    return, result is set to NULL.

  . . .

    An optional argument that can be either 1 or 0. If you specify
    1, the directory specification is returned in OpenVMS format. If
    you specify 0, the directory specification (pathname) is returned
    in UNIX style format. If you omit this argument, the function
    returns the directory specification according to your current
    command-language interpreter.