diff --git a/configure.ac b/configure.ac
index fd7b263..a341eac 100644
--- a/configure.ac
+++ b/configure.ac
@@ -53,7 +53,7 @@ AC_ARG_ENABLE([mysql],
 )
 
 # Checks for header files.
-AC_CHECK_HEADERS([arpa/inet.h netinet/in.h stdint.h stdlib.h syslog.h unistd.h])
+AC_CHECK_HEADERS([arpa/inet.h netinet/in.h inttypes.h stdlib.h syslog.h unistd.h])
 
 # Checks for typedefs, structures, and compiler characteristics.
 AC_C_INLINE
diff --git a/src/addrwatch.c b/src/addrwatch.c
index e0d5a46..98dd73d 100644
--- a/src/addrwatch.c
+++ b/src/addrwatch.c
@@ -3,7 +3,7 @@
 #include <limits.h>
 #include <pwd.h>
 #include <signal.h>
-#include <stdint.h>
+#include <inttypes.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
diff --git a/src/addrwatch_stdout.c b/src/addrwatch_stdout.c
index 8c8a6e9..7ba0938 100644
--- a/src/addrwatch_stdout.c
+++ b/src/addrwatch_stdout.c
@@ -16,7 +16,7 @@ void process_entry(struct shm_log_entry *e, void *arg)
 		ip4_ntoa(e->ip_address, ip_str);
 	}
 
-	printf("%lu %s %u %s %s %s\n", e->timestamp, e->interface, e->vlan_tag,
+	printf("%" PRIu64 " %s %" PRIu16 " %s %s %s\n", e->timestamp, e->interface, e->vlan_tag,
 		mac_str, ip_str, pkt_origin_str[e->origin]);
 }
 
diff --git a/src/addrwatch_syslog.c b/src/addrwatch_syslog.c
index f9da09e..c82fd01 100644
--- a/src/addrwatch_syslog.c
+++ b/src/addrwatch_syslog.c
@@ -18,7 +18,7 @@ void process_entry(struct shm_log_entry *e, void *arg)
 		ip4_ntoa(e->ip_address, ip_str);
 	}
 
-	syslog(LOG_INFO, "%lu %s %u %s %s %s", e->timestamp, e->interface,
+	syslog(LOG_INFO, "%" PRIu64 " %s %" PRIu16 " %s %s %s", e->timestamp, e->interface,
 		e->vlan_tag, mac_str, ip_str, pkt_origin_str[e->origin]);
 }
 
diff --git a/src/base64.h b/src/base64.h
index 25df03c..6492529 100644
--- a/src/base64.h
+++ b/src/base64.h
@@ -2,7 +2,7 @@
 #define BASE64_H
 
 #include "addrwatch.h"
-#include <stdint.h>
+#include <inttypes.h>
 
 void base64_encode(const uint8_t *src, char *dst, int ssize, int dsize);
 char *base64_encode_packet(struct pkt *p);
diff --git a/src/common.h b/src/common.h
index 8381827..e4aa298 100644
--- a/src/common.h
+++ b/src/common.h
@@ -2,7 +2,7 @@
 #define COMMON_H
 
 #include <arpa/inet.h>
-#include <stdint.h>
+#include <inttypes.h>
 #include <stdio.h>
 #include <sys/socket.h>
 
diff --git a/src/mcache.h b/src/mcache.h
index 78db3b5..1388f5a 100644
--- a/src/mcache.h
+++ b/src/mcache.h
@@ -6,7 +6,7 @@
 
 #include <sys/types.h>
 #include <netinet/if_ether.h>
-#include <stdint.h>
+#include <inttypes.h>
 
 struct mcache_node {
 	uint8_t l2_addr[ETHER_ADDR_LEN];
diff --git a/src/output_flatfile.c b/src/output_flatfile.c
index 412fff9..c4be71e 100644
--- a/src/output_flatfile.c
+++ b/src/output_flatfile.c
@@ -22,8 +22,8 @@ void output_flatfile_reload()
 void output_flatfile_save(struct pkt *p, char *mac_str, char *ip_str)
 {
 	if (cfg.data_fd) {
-		fprintf(cfg.data_fd, "%lu %s %u %s %s %s\n",
-			p->pcap_header->ts.tv_sec, p->ifc->name, p->vlan_tag,
+		fprintf(cfg.data_fd, "%" PRIu64 " %s %" PRIu16 " %s %s %s\n",
+			(uint64_t)p->pcap_header->ts.tv_sec, p->ifc->name, p->vlan_tag,
 			mac_str, ip_str, pkt_origin_str[p->origin]);
 		fflush(cfg.data_fd);
 	}
diff --git a/src/parse.c b/src/parse.c
index 2b352f5..92856ea 100644
--- a/src/parse.c
+++ b/src/parse.c
@@ -1,4 +1,4 @@
-//#include <stdint.h>
+//#include <inttypes.h>
 //#include <stdio.h>
 //#include <stdlib.h>
 
diff --git a/src/shm.h b/src/shm.h
index 1a154e2..7e12737 100644
--- a/src/shm.h
+++ b/src/shm.h
@@ -4,7 +4,7 @@
 #include <net/if.h>
 #include <netinet/in.h>
 #include <netinet/if_ether.h>
-#include <stdint.h>
+#include <inttypes.h>
 #include <sys/socket.h>
 
 #define DEFAULT_SHM_LOG_NAME "/addrwatch-shm-log"
diff --git a/src/shm_client.c b/src/shm_client.c
index 930467b..f070695 100644
--- a/src/shm_client.c
+++ b/src/shm_client.c
@@ -2,7 +2,7 @@
 
 #include <fcntl.h>
 #include <net/if.h>
-#include <stdint.h>
+#include <inttypes.h>
 #include <stdlib.h>
 #include <sys/mman.h>
 #include <sys/stat.h>
diff --git a/src/storage.c b/src/storage.c
index f0c68fb..2984296 100644
--- a/src/storage.c
+++ b/src/storage.c
@@ -129,7 +129,7 @@ void save_pairing(struct pkt *p)
 
 	output_shm_save(p, mac_str, ip_str);
 	if (!cfg.quiet) {
-		printf("%lu %s %u %s %s %s\n", tstamp, p->ifc->name,
+		printf("%" PRIu64 " %s %" PRIu16 " %s %s %s\n", (uint64_t)tstamp, p->ifc->name,
 			p->vlan_tag, mac_str, ip_str, pkt_origin_str[p->origin]);
 		fflush(stdout);
 	}
diff --git a/src/util.h b/src/util.h
index 7936137..757ad2d 100644
--- a/src/util.h
+++ b/src/util.h
@@ -5,7 +5,7 @@
 #include "config.h"
 #endif
 
-#include <stdint.h>
+#include <inttypes.h>
 #include <stdio.h>
 
 #include <syslog.h>