Index: src/tk/tkoption.c
--- src/tk/tkoption.c.orig
+++ src/tk/tkoption.c
@@ -21,6 +21,7 @@ static char rcsid[] = "$Header: /user6/ouster/wish/RCS
 
 #include "tkconfig.h"
 #include "tkint.h"
+#include <unistd.h>
 
 /*
  * The option database is stored as one tree for each main window.
@@ -872,7 +873,7 @@ ReadOptionFile(interp, tkwin, fileName, priority)
 #ifdef MSDOS
     if (read(fileId, buffer, (int) statBuf.st_size) < 0) {
 #else
-    if (read(fileId, buffer, (int) statBuf.st_size) != statBuf.st_size) {
+    if (read(fileId, buffer, statBuf.st_size) != statBuf.st_size) {
 #endif
 	Tcl_AppendResult(interp, "error reading file \"", fileName, "\"",
 		(char *) NULL);
