1 files changed, 5 insertions, 2 deletions

diff --git a/gzio.c b/gzio.c
index b069b7a..7e90f49 100644
--- a/gzio.c
+++ b/gzio.c
@@ -489,6 +489,9 @@ int ZEXPORT gzread (file, buf, len)
     }
     s->crc = crc32(s->crc, start, (uInt)(s->stream.next_out - start));
 
+    if (len == s->stream.avail_out &&
+        (s->z_err == Z_DATA_ERROR || s->z_err == Z_ERRNO))
+        return -1;
     return (int)(len - s->stream.avail_out);
 }
 
@@ -975,9 +978,9 @@ int ZEXPORT gzclose (file)
 #endif
 
 /* ===========================================================================
-     Returns the error message for the last error which occured on the
+     Returns the error message for the last error which occurred on the
    given compressed file. errnum is set to zlib error number. If an
-   error occured in the file system and not in the compression library,
+   error occurred in the file system and not in the compression library,
    errnum is set to Z_ERRNO and the application may consult errno
    to get the exact error code.
 */