Function writeAll

lib/internal/fs/promises.js:763–793

(buf, offset, length, position, signal)

    // Write a single buffer with EAGAIN retry (up to 5 retries).
    async function writeAll(buf, offset, length, position, signal) {
      asyncPending = true;
      try {
        let retries = 0;
        while (length > 0) {
          const bytesWritten = (await PromisePrototypeThen(
            binding.writeBuffer(fd, buf, offset, length, position,
                                kUsePromises),
            undefined,
            handleErrorFromBinding,
          )) || 0;

          signal?.throwIfAborted();

          if (bytesWritten === 0) {
            if (++retries > 5) {
              throw new ERR_OPERATION_FAILED('write failed after retries');
            }
          } else {
            retries = 0;
          }

          totalBytesWritten += bytesWritten;
          offset += bytesWritten;
          length -= bytesWritten;
          if (position >= 0) position += bytesWritten;
        }
      } finally {
        asyncPending = false;
      }
    }

    // Writev with EAGAIN retry. On partial write, concatenates remaining
    // buffers and falls back to writeAll (same approach as WriteStream).