diff --git a/lib/libsysdecode/mktables b/lib/libsysdecode/mktables
--- a/lib/libsysdecode/mktables
+++ b/lib/libsysdecode/mktables
@@ -127,7 +127,7 @@
 gen_table "schedpolicy"     "SCHED_[A-Z]+[[:space:]]+[0-9]+"               "sys/sched.h"
 gen_table "sendfileflags"   "SF_[A-Z]+[[:space:]]+[0-9]+"                  "sys/socket.h"
 gen_table "shmatflags"      "SHM_[A-Z]+[[:space:]]+[0-9]{6}"               "sys/shm.h"
-gen_table "shutdownhow"     "SHUT_[A-Z]+[[:space:]]+[0-9]+"                "sys/socket.h"
+gen_table "shutdownhow"     "SHUT_[A-Z]+[[:space:]]+SHUT_[A-Z]+"           "sys/socket.h"
 gen_table "sigbuscode"      "BUS_[A-Z]+[[:space:]]+[0-9]+"                 "sys/signal.h"
 gen_table "sigchldcode"     "CLD_[A-Z]+[[:space:]]+[0-9]+"                 "sys/signal.h"
 gen_table "sigfpecode"      "FPE_[A-Z]+[[:space:]]+[0-9]+"                 "sys/signal.h"