file_ptr

    A file pointer.

 offset

    The offset, specified in bytes. The off_t data type is either a
    32-bit or 64-bit integer. The 64-bit interface allows for file
    sizes greater than 2 GB, and can be selected at compile time by
    defining the _LARGEFILE feature-test macro as follows:

    CC/DEFINE=_LARGEFILE

 direction

    An integer indicating the position to which the offset is added
    to calculate the new position. The new position is the beginning
    of the file if direction is SEEK_SET, the current value of the
    file position indicator if direction is SEEK_CUR, or end-of-file
    if direction is SEEK_END.