diff --git a/test/ascii_tag.c b/test/ascii_tag.c
index 124ef29a..6337900b 100644
--- a/test/ascii_tag.c
+++ b/test/ascii_tag.c
@@ -1,4 +1,4 @@
-/* $Id: ascii_tag.c,v 1.7 2008-04-15 13:32:12 dron Exp $ */
+/* $Id: ascii_tag.c,v 1.8 2013-12-17 14:41:57 bfriesen Exp $ */
 
 /*
  * Copyright (c) 2004, Andrey Kiselev  <dron@ak4719.spb.edu>
@@ -129,7 +129,7 @@ main()
 	}
 
 	/* Write dummy pixel data. */
-	if (!TIFFWriteScanline(tif, buf, 0, 0) < 0) {
+	if (TIFFWriteScanline(tif, buf, 0, 0) == -1) {
 		fprintf (stderr, "Can't write image data.\n");
 		goto failure;
 	}
diff --git a/test/custom_dir.c b/test/custom_dir.c
index 8e448306..acf55ce5 100644
--- a/test/custom_dir.c
+++ b/test/custom_dir.c
@@ -1,4 +1,4 @@
-/* $Id: custom_dir.c,v 1.2 2012-06-06 05:26:37 fwarmerdam Exp $ */
+/* $Id: custom_dir.c,v 1.3 2013-12-17 14:41:58 bfriesen Exp $ */
 
 /*
  * Copyright (c) 2012, Frank Warmerdam <warmerdam@pobox.com>
@@ -108,7 +108,7 @@ main()
 	}
 
 	/* Write dummy pixel data. */
-	if (!TIFFWriteScanline(tif, buf, 0, 0) < 0) {
+	if (TIFFWriteScanline(tif, buf, 0, 0) == -1) {
 		fprintf (stderr, "Can't write image data.\n");
 		goto failure;
 	}
diff --git a/test/long_tag.c b/test/long_tag.c
index 5c3c6800..ab1440af 100644
--- a/test/long_tag.c
+++ b/test/long_tag.c
@@ -1,4 +1,4 @@
-/* $Id: long_tag.c,v 1.4 2008-03-28 01:42:06 bfriesen Exp $ */
+/* $Id: long_tag.c,v 1.5 2013-12-17 14:41:58 bfriesen Exp $ */
 
 /*
  * Copyright (c) 2004, Andrey Kiselev  <dron@ak4719.spb.edu>
@@ -111,7 +111,7 @@ main(int argc, char **argv)
 	}
 
 	/* Write dummy pixel data. */
-	if (!TIFFWriteScanline(tif, buf, 0, 0) < 0) {
+	if (TIFFWriteScanline(tif, buf, 0, 0) == -1) {
 		fprintf (stderr, "Can't write image data.\n");
 		goto failure;
 	}
diff --git a/test/rewrite_tag.c b/test/rewrite_tag.c
index 1023f166..de0b5514 100644
--- a/test/rewrite_tag.c
+++ b/test/rewrite_tag.c
@@ -1,4 +1,4 @@
-/* $Id: rewrite_tag.c,v 1.5 2012-06-13 04:38:55 fwarmerdam Exp $ */
+/* $Id: rewrite_tag.c,v 1.6 2013-12-17 14:41:58 bfriesen Exp $ */
 
 /*
  * Copyright (c) 2007, Frank Warmerdam <warmerdam@pobox.com>
@@ -191,7 +191,7 @@ int rewrite_test( const char *filename, int length, int bigtiff,
 
     for (i = 0; i < length; i++ )
     {
-        if( !TIFFWriteScanline( tif, buf, i, 0 ) )
+        if( TIFFWriteScanline( tif, buf, i, 0 ) == -1 )
         {
             fprintf (stderr, "Can't write image data.\n");
             goto failure;
diff --git a/test/short_tag.c b/test/short_tag.c
index 7b832281..efc7da5b 100644
--- a/test/short_tag.c
+++ b/test/short_tag.c
@@ -1,4 +1,4 @@
-/* $Id: short_tag.c,v 1.8 2008-04-15 14:20:30 dron Exp $ */
+/* $Id: short_tag.c,v 1.9 2013-12-17 14:41:58 bfriesen Exp $ */
 
 /*
  * Copyright (c) 2004, Andrey Kiselev  <dron@ak4719.spb.edu>
@@ -140,7 +140,7 @@ main()
 	}
 
 	/* Write dummy pixel data. */
-	if (!TIFFWriteScanline(tif, buf, 0, 0) < 0) {
+	if (TIFFWriteScanline(tif, buf, 0, 0) == -1) {
 		fprintf (stderr, "Can't write image data.\n");
 		goto failure;
 	}
diff --git a/test/strip.c b/test/strip.c
index b01e8fa0..59422262 100644
--- a/test/strip.c
+++ b/test/strip.c
@@ -1,4 +1,4 @@
-/* $Id: strip.c,v 1.4 2008-03-28 01:42:06 bfriesen Exp $ */
+/* $Id: strip.c,v 1.5 2013-12-17 14:41:58 bfriesen Exp $ */
 
 /*
  * Copyright (c) 2004, Andrey Kiselev  <dron@ak4719.spb.edu>
@@ -277,7 +277,7 @@ write_scanlines(TIFF *tif, const tdata_t array, const tsize_t size)
 	}
 
 	for (offset = 0, row = 0; row < length; offset+=scanlinesize, row++) {
-		if (TIFFWriteScanline(tif, (char *)array + offset, row, 0) < 0) {
+		if (TIFFWriteScanline(tif, (char *)array + offset, row, 0) == -1) {
 			fprintf (stderr,
 				 "Can't write image data at row %lu.\n", (long) row);
 			return -1;