path

    The name of a file that is to be truncated. This argument must
    point to a pathname that names a regular file for which the
    calling process has write permission.

 length

    The new length of the file, in bytes. The off_t type of length
    is either a 64-bit or 32-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