-#define RESADFLT 0 /* reserved addressing fault */
-#define PRIVINFLT 1 /* privileged instruction fault */
-#define BPTFLT 2 /* bpt instruction fault */
-#define XFCFLT 3 /* xfc instruction fault */
-#define RESOPFLT 4 /* reserved operand fault */
-#define SYSCALL 5 /* chmk instruction (syscall trap) */
-#define ARITHTRAP 6 /* arithmetic trap */
-#define RESCHED 7 /* software level 1 trap
- (reschedule trap) */
-#define SEGFLT 8 /* segmentation fault */
-#define PROTFLT 9 /* protection fault */
-#define TRCTRAP 10 /* trace trap */
-#define COMPATFLT 11 /* compatibility mode fault */
-#define PAGEFLT 12 /* page fault */
-#define TABLEFLT 13 /* page table fault */
+/* The first three constant values are known to the real world <signal.h> */
+#define T_RESADFLT 0 /* reserved addressing fault */
+#define T_PRIVINFLT 1 /* privileged instruction fault */
+#define T_RESOPFLT 2 /* reserved operand fault */
+/* End of known constants */
+#define T_BPTFLT 3 /* bpt instruction fault */
+#define T_XFCFLT 4 /* xfc instruction fault */
+#define T_SYSCALL 5 /* chmk instruction (syscall trap) */
+#define T_ARITHTRAP 6 /* arithmetic trap */
+#define T_ASTFLT 7 /* software level 2 trap (ast deliv) */
+#define T_SEGFLT 8 /* segmentation fault */
+#define T_PROTFLT 9 /* protection fault */
+#define T_TRCTRAP 10 /* trace trap */
+#define T_COMPATFLT 11 /* compatibility mode fault */
+#define T_PAGEFLT 12 /* page fault */
+#define T_TABLEFLT 13 /* page table fault */