diff --git a/sbin/kldconfig/kldconfig.c b/sbin/kldconfig/kldconfig.c
index bd4015df6b10..21f4d1c390dd 100644
--- a/sbin/kldconfig/kldconfig.c
+++ b/sbin/kldconfig/kldconfig.c
@@ -142,7 +142,7 @@ setpath(struct pathhead *pathq)
 	if (sysctl(mib, miblen, NULL, NULL, newpath, strlen(newpath)+1) == -1)
 		err(1, "setting path: sysctl(%s)", pathctl);
 
-	if (modpath)
+	if (modpath != NULL)
 		free(modpath);
 	modpath = newpath;
 }
diff --git a/sbin/kldstat/kldstat.c b/sbin/kldstat/kldstat.c
index 3e1adee83913..be699d5b8690 100644
--- a/sbin/kldstat/kldstat.c
+++ b/sbin/kldstat/kldstat.c
@@ -92,7 +92,7 @@ main(int argc, char** argv)
     int c;
     int verbose = 0;
     int fileid = 0;
-    char* filename = 0;
+    char* filename = NULL;
 
     while ((c = getopt(argc, argv, "i:n:v")) != -1)
 	switch (c) {
@@ -114,13 +114,13 @@ main(int argc, char** argv)
     if (argc != 0)
 	usage();
 
-    if (filename) {
+    if (filename != NULL) {
 	if ((fileid = kldfind(filename)) < 0)
 	    err(1, "can't find file %s", filename);
     }
 
     printf("Id Refs Address%*c Size     Name\n", POINTER_WIDTH - 7, ' ');
-    if (fileid)
+    if (fileid != 0)
 	printfile(fileid, verbose);
     else
 	for (fileid = kldnext(0); fileid > 0; fileid = kldnext(fileid))
diff --git a/sbin/kldunload/kldunload.c b/sbin/kldunload/kldunload.c
index e8b8daf17d10..9893f3aa8d2b 100644
--- a/sbin/kldunload/kldunload.c
+++ b/sbin/kldunload/kldunload.c
@@ -50,7 +50,7 @@ main(int argc, char** argv)
     int c;
     int verbose = 0;
     int fileid = 0;
-    char* filename = 0;
+    char* filename = NULL;
 
     while ((c = getopt(argc, argv, "i:n:v")) != -1)
 	switch (c) {
@@ -71,18 +71,18 @@ main(int argc, char** argv)
     argc -= optind;
     argv += optind;
 
-    if (!fileid && !filename && (argc == 1)) {
+    if (fileid == 0 && filename == NULL && (argc == 1)) {
 	filename = *argv;
 	argc--;
     }
     
-    if (argc != 0 || (fileid && filename))
+    if (argc != 0 || (fileid != 0 && filename != NULL))
 	usage();
 
-    if (fileid == 0 && filename == 0)
+    if (fileid == 0 && filename == NULL)
 	usage();
 
-    if (filename) {
+    if (filename != NULL) {
 	if ((fileid = kldfind(filename)) < 0)
 	    err(1, "can't find file %s", filename);
     }