diff --git a/captype.c b/captype.c
index 5204007875..6a0098788f 100644
--- a/captype.c
+++ b/captype.c
@@ -133,18 +133,15 @@ main(int argc, char *argv[])
             case 'h':
                 show_help_header("Print the file types of capture files.");
                 print_usage(stdout);
-                exit(0);
-                break;
+                return EXIT_SUCCESS;
 
             case 'v':
                 show_version();
-                exit(0);
-                break;
+                return EXIT_SUCCESS;
 
             case '?':              /* Bad flag - print usage message */
                 print_usage(stderr);
-                exit(1);
-                break;
+                return EXIT_FAILURE;
         }
     }
 
diff --git a/epan/dtd.h b/epan/dtd.h
index f835e54fba..eefcfbae36 100644
--- a/epan/dtd.h
+++ b/epan/dtd.h
@@ -17,7 +17,6 @@
 
 #include <glib.h>
 #include <stdbool.h>
-#include <stdlib.h> /* exit() */
 #include "ws_attributes.h"
 
 typedef struct _dtd_build_data_t {
diff --git a/epan/exntest.c b/epan/exntest.c
index 0fe81645ed..0ae1afdd73 100644
--- a/epan/exntest.c
+++ b/epan/exntest.c
@@ -211,7 +211,7 @@ int main(void)
     except_init();
     run_tests();
     except_deinit();
-    exit(failed?1:0);
+    return failed ? EXIT_FAILURE:EXIT_SUCCESS;
 }
 
 /*
diff --git a/epan/tvbtest.c b/epan/tvbtest.c
index add2380a56..84faca1995 100644
--- a/epan/tvbtest.c
+++ b/epan/tvbtest.c
@@ -817,7 +817,7 @@ main(void)
 	varint_tests();
 	zstd_tests ();
 	except_deinit();
-	exit(failed?1:0);
+	return failed ? EXIT_FAILURE : EXIT_SUCCESS;
 }
 
 /*
diff --git a/mmdbresolve.c b/mmdbresolve.c
index 5669e89ea7..6fc64d2ee9 100644
--- a/mmdbresolve.c
+++ b/mmdbresolve.c
@@ -53,11 +53,6 @@ static const char **lookup_keys[] = {
     empty_key
 };
 
-static void exit_err(void) {
-    fprintf(stderr, "Usage: mmdbresolve -f db_file [-f db_file ...]\n");
-    exit(1);
-}
-
 int
 main(int argc, char *argv[])
 {
@@ -110,7 +105,8 @@ main(int argc, char *argv[])
     fflush(stdout);
 
     if (arg_idx != argc || mmdb_count < 1) {
-        exit_err();
+        fprintf(stderr, "Usage: mmdbresolve -f db_file [-f db_file ...]\n");
+        return EXIT_FAILURE;
     }
 
     int in_items = 0;
@@ -186,7 +182,7 @@ main(int argc, char *argv[])
 
     free(mmdbs);
 
-    return 0;
+    return EXIT_SUCCESS;
 }
 
 /*