diff --git a/netbsd_exporter.c b/netbsd_exporter.c
index 20aa67e..499f469 100644
--- a/netbsd_exporter.c
+++ b/netbsd_exporter.c
@@ -53,11 +53,11 @@
 #include "netbsd_exporter.h"
 #include "version.h"
 
-void print_filesystem_metric(const char* metric, const char* device, const char* mountpoint, long value) {
-    printf("netbsd_fs_%s_bytes{device=\"%s\",mountpoint=\"%s\"} %ld\n", metric, device, mountpoint, value);
+void print_filesystem_metric(const char* metric, const char* device, const char* mountpoint, unsigned long long value) {
+    printf("netbsd_fs_%s_bytes{device=\"%s\",mountpoint=\"%s\"} %llu\n", metric, device, mountpoint, value);
 }
 
-void print_disk_io_metric(const char* device, long long unsigned int rbytes, long long unsigned int wbytes) {
+void print_disk_io_metric(const char* device, unsigned long long rbytes, unsigned long long wbytes) {
     printf("netbsd_dk_read_bytes{device=\"%s\"} %llu\n", device, rbytes);
     printf("netbsd_dk_write_bytes{device=\"%s\"} %llu\n", device, wbytes);
 }
diff --git a/netbsd_exporter.h b/netbsd_exporter.h
index 63c3007..fc4c7dc 100644
--- a/netbsd_exporter.h
+++ b/netbsd_exporter.h
@@ -31,13 +31,13 @@ const char *program_name = "netbsd_exporter";
 int option_http_header = 1;
 int option_syslog = 1;
 
-void print_filesystem_metric(const char*, const char*, const char*, long );
+void print_filesystem_metric(const char*, const char*, const char*, unsigned long long);
 
-void print_disk_io_metric(const char*, long long unsigned int, long long unsigned int );
+void print_disk_io_metric(const char*, unsigned long long, unsigned long long);
 
 void print_load_metric(const char*, double );
 
-void print_network_metric(const char*, unsigned long long, unsigned long long, unsigned long long );
+void print_network_metric(const char*, unsigned long long, unsigned long long, unsigned long long);
 
 void print_memory_metric(const char*, long );