+ if (ret >= 0)
+ return 1;
+ ret = -ERRNO_TO_PARA_ERROR(errno);
+ PARA_ERROR_LOG("failed to rename %s -> %s\n", oldpath, newpath);
+ return ret;
+}
+
+/**
+ * Write an array of buffers, handling non-fatal errors.
+ *
+ * \param fd The file descriptor to write to.
+ * \param iov Pointer to one or more buffers.
+ * \param iovcnt The number of buffers.
+ *
+ * EAGAIN, EWOULDBLOCK and EINTR are not considered error conditions. If a
+ * write operation fails with EAGAIN or EWOULDBLOCK, the number of bytes that
+ * have been written so far is returned. In the EINTR case the operation is
+ * retried. Short writes are handled by issuing a subsequent write operation
+ * for the remaining part.
+ *
+ * \return Negative on fatal errors, number of bytes written else.
+ *
+ * For blocking file descriptors, this function returns either the sum of all
+ * buffer sizes or a negative error code which indicates the fatal error that
+ * caused a write call to fail.
+ *
+ * For nonblocking file descriptors there is a third possibility: Any
+ * non-negative return value less than the sum of the buffer sizes indicates
+ * that a write operation returned EAGAIN/EWOULDBLOCK.
+ *
+ * \sa writev(2), \ref xwrite().
+ */
+int xwritev(int fd, struct iovec *iov, int iovcnt)
+{
+ size_t written = 0;
+ int i;
+ struct iovec saved_iov, *curiov;
+
+ i = 0;
+ curiov = iov;
+ saved_iov = *curiov;
+ while (i < iovcnt && curiov->iov_len > 0) {
+ ssize_t ret = writev(fd, curiov, iovcnt - i);
+ if (ret >= 0) {
+ written += ret;
+ while (ret > 0) {
+ if (ret < curiov->iov_len) {
+ curiov->iov_base += ret;
+ curiov->iov_len -= ret;
+ break;
+ }
+ ret -= curiov->iov_len;
+ *curiov = saved_iov;
+ i++;
+ if (i >= iovcnt)
+ return written;
+ curiov++;
+ saved_iov = *curiov;
+ }
+ continue;
+ }
+ if (errno == EINTR)
+ /*
+ * The write() call was interrupted by a signal before
+ * any data was written. Try again.
+ */
+ continue;
+ if (errno == EAGAIN || errno == EWOULDBLOCK)
+ /*
+ * We don't consider this an error. Note that POSIX
+ * allows either error to be returned, and does not
+ * require these constants to have the same value.
+ */
+ return written;
+ /* fatal error */
+ return -ERRNO_TO_PARA_ERROR(errno);