Bug fixes, when tried on QNX/Neutrino.

@@ -134,10 +134,12 @@ _file_write (stream_t stream, const char *iptr, size_t isize,
     }
 
   n = fwrite (iptr, sizeof(char), isize, fs->file);
-  if (n == 0)
+  if (n != isize)
     {
-      if (ferror (fs->file))
-	err = errno;
+      if (feof (fs->file) == 0)
+	err = EIO;
+      clearerr(fs->file);
+      n = 0;
     }
   else
     fs->offset += n;

@@ -489,6 +489,7 @@ mbox_scan0 (mailbox_t mailbox, size_t msgno, size_t *pcount, int do_notif)
               mum->header_from = total - n;
               mum->header_from_end = total;
 	      mum->body_end = mum->body = 0;
+	      mum->attr_flags = 0;
 	      lines = 0;
 	      sfield = NULL;
 	      for (j = 0; j < HDRSIZE; j++)
@@ -645,7 +646,7 @@ mbox_scan0 (mailbox_t mailbox, size_t msgno, size_t *pcount, int do_notif)
 	  }
 	mum->uid = ouid = uid;
       }
-    if (uid > mud->messages_count)
+    if (uid >= mud->uidnext)
       {
 	char u[64];
 	mud->uidnext = uid + 1;

@@ -369,7 +369,7 @@ stream_write (stream_t os, const char *buf, size_t count,
   while (nleft > 0)
     {
       err = os->_write (os, buf, nleft, offset, &nwriten);
-      if (err != 0)
+      if (err != 0 || nwriten == 0)
         break;
       nleft -= nwriten;
       total += nwriten;