/* Returns the number of bytes written, or -1 upon failure. */
ssize_t written = write(port->fd, buf, count);
- if (written < 0)
- RETURN_FAIL("write() failed");
- else
+ if (written < 0) {
+ if (errno == EAGAIN)
+ // Buffer is full, no bytes written.
+ RETURN_INT(0);
+ else
+ RETURN_FAIL("write() failed");
+ } else {
RETURN_INT(written);
+ }
#endif
}