diff --git a/include/asm.h b/include/asm.h
index 05f9c34..ce6c16d 100644
--- a/include/asm.h
+++ b/include/asm.h
@@ -38,6 +38,11 @@
 //
 #define interrupt(n) asm volatile ("int %0" : : "N" (n) : "cc", "memory")
 
+//
+// Trigger a system call
+//
+#define syscall(n) asm volatile ("movq %0, %rdi\nint $0x80" : : "N" (n) : "cc", "memory")
+
 //
 // Returns whether IRQs are enabled
 //