diff --git a/kernel/config.c b/kernel/config.c
index f7723b5..767788e 100644
--- a/kernel/config.c
+++ b/kernel/config.c
@@ -649,7 +649,7 @@ VOID DoConfig(int nPass)
 
     for (pLine = szLine;;)
     {
-      if (read(nFileDesc, pLine, 1) <= 0)
+      if (read(nFileDesc, pLine, 1) == 0)
       {
         bEof = TRUE;
         break;
diff --git a/kernel/fatfs.c b/kernel/fatfs.c
index 71240b0..589a4ec 100644
--- a/kernel/fatfs.c
+++ b/kernel/fatfs.c
@@ -355,7 +355,7 @@ f_node_ptr split_path(char * path, char * fcbname)
   /* If the fd was invalid because it was out of range or the     */
   /* requested file was not open, tell the caller and exit...     */
   /* note: an invalid fd is indicated by a 0 return               */
-  if (fnp == (f_node_ptr) 0 || fnp->f_count <= 0)
+  if (fnp == (f_node_ptr) 0 || fnp->f_count == 0)
   {
     dir_close(fnp);
     return (f_node_ptr) 0;
@@ -2174,7 +2174,7 @@ f_node_ptr xlt_fd(int fd)
     if (fnp != (f_node_ptr)0)
     {
       fmemcpy(fnp, &f_nodes[fd], sizeof(*fnp));
-      if (fnp->f_count <= 0)
+      if (fnp->f_count == 0)
       {
         release_near_f_node(fnp);
         fnp = (f_node_ptr) 0;
diff --git a/kernel/inthndlr.c b/kernel/inthndlr.c
index 8017ba8..3ed06bc 100644
--- a/kernel/inthndlr.c
+++ b/kernel/inthndlr.c
@@ -371,7 +371,7 @@ int int21_fat32(lregs *r)
                 SectorBlock->nblks, mode);
     
       if (mode == DSKWRITEINT26)
-        if (r->AX <= 0)
+        if (r->AX == 0)
           setinvld(r->DL - 1);
       
       if (r->AX > 0)