diff --git a/src/util.c b/src/util.c
index ab49890..7332891 100644
--- a/src/util.c
+++ b/src/util.c
@@ -203,7 +203,7 @@ tape_fill_input_buffer (int in_des, int num_bytes)
       get_next_reel (in_des);
       input_size = rmtread (in_des, input_buffer, num_bytes);
     }
-  if (input_size < 0)
+  if (input_size == SAFE_READ_ERROR)
     error (1, errno, _("read error"));
   if (input_size == 0)
     {
@@ -224,7 +224,7 @@ disk_fill_input_buffer (int in_des, off_t num_bytes)
   in_buff = input_buffer;
   num_bytes = (num_bytes < DISK_IO_BLOCK_SIZE) ? num_bytes : DISK_IO_BLOCK_SIZE;
   input_size = read (in_des, input_buffer, num_bytes);
-  if (input_size < 0) 
+  if (input_size == SAFE_READ_ERROR)
     {
       input_size = 0;
       return (-1);