diff --git a/userland/posix/environ.c b/userland/posix/environ.c
new file mode 100644
index 0000000..39ef1cb
--- /dev/null
+++ b/userland/posix/environ.c
@@ -0,0 +1,15 @@
+/* Print all environment variables. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+extern char **environ;
+
+int main(void) {
+    char **env = environ;
+    while (*env) {
+        printf("%s\n", *env);
+        env++;
+    }
+    return EXIT_SUCCESS;
+}