Method WriteAt

cpp/src/arrow/io/file.cc:747–758

bool MemoryMappedFile::supports_zero_copy() const { return true; }

Status MemoryMappedFile::WriteAt(int64_t position, const void* data, int64_t nbytes) {
  RETURN_NOT_OK(memory_map_->CheckClosed());
  std::lock_guard<std::mutex> guard(memory_map_->write_lock());

  if (!memory_map_->opened() || !memory_map_->writable()) {
    return Status::IOError("Unable to write");
  }
  RETURN_NOT_OK(internal::ValidateWriteRange(position, nbytes, memory_map_->size()));

  RETURN_NOT_OK(memory_map_->Seek(position));
  return WriteInternal(data, nbytes);
}

Status MemoryMappedFile::Write(const void* data, int64_t nbytes) {
  RETURN_NOT_OK(memory_map_->CheckClosed());