diff --git a/extract/ExtBasic.c b/extract/ExtBasic.c
index 7ca31c2c..e436368a 100644
--- a/extract/ExtBasic.c
+++ b/extract/ExtBasic.c
@@ -389,7 +389,7 @@ extBasic(def, outFile)
 	    if (propfound)
 	    {
 		token = strtok(NULL, " ");
-		if ((token == NULL) || !sscanf(token, "%d", &llx))
+		if ((token == NULL) || (sscanf(token, "%d", &llx) != 1))
 		    propfound = FALSE;
 		else
 		    llx *= ExtCurStyle->exts_unitsPerLambda;
@@ -397,7 +397,7 @@ extBasic(def, outFile)
 	    if (propfound)
 	    {
 		token = strtok(NULL, " ");
-		if ((token == NULL) || !sscanf(token, "%d", &lly))
+		if ((token == NULL) || (sscanf(token, "%d", &lly) != 1))
 		    propfound = FALSE;
 		else
 		    lly *= ExtCurStyle->exts_unitsPerLambda;