3 files changed, 20 insertions, 0 deletions
diff --git a/src/util.c b/src/util.c
index e7a3823..e295cb6 100644
--- a/src/util.c
+++ b/src/util.c
@@ -13,6 +13,9 @@
 const size_t
 NULL_TERMINATOR = sizeof((char)'\0');
 
+const int
+EXIT_USAGE = 2;
+
 int
 slurp(const char *const filename, char **out) {
 	int rc = -1;
diff --git a/src/util.h b/src/util.h
index ca6ba3f..f1bace9 100644
--- a/src/util.h
+++ b/src/util.h
@@ -1,6 +1,9 @@
 extern const size_t
 NULL_TERMINATOR;
 
+extern const int
+EXIT_USAGE;
+
 int
 slurp(const char *const filename, char **out);
 
diff --git a/tests/util.c b/tests/util.c
index 662ccc8..bda7606 100644
--- a/tests/util.c
+++ b/tests/util.c
@@ -6,6 +6,18 @@
 #include "slurp.h"
 
 
+static void
+test_EXIT_USAGE(void) {
+	test_start("EXIT_USAGE");
+
+	{
+		testing("it is different that EXIT_SUCCESS and EXIT_FAILURE");
+		assert(EXIT_USAGE != EXIT_SUCCESS);
+		assert(EXIT_USAGE != EXIT_FAILURE);
+		test_ok();
+	}
+}
+
 static int
 test_slurp(void) {
 	int rc = -1;
@@ -99,6 +111,8 @@ int
 main(void) {
 	int rc = -1;
 
+	test_EXIT_USAGE();
+
 	if (test_slurp()) {
 		logerr("test_slurp()");
 		goto out;