Export a type for POSIX SHM file descriptors via kern.proc.filedesc as

used by procstat, or SHM descriptors will show up as type unknown in
userspace.

sys/kern/kern_descrip.c

@@ -2514,6 +2514,10 @@ sysctl_kern_proc_filedesc(SYSCTL_HANDLER_ARGS)
 			kif->kf_type = KF_TYPE_MQUEUE;
 			break;
 
+		case DTYPE_SHM:
+			kif->kf_type = KF_TYPE_SHM;
+			break;
+
 		default:
 			kif->kf_type = KF_TYPE_UNKNOWN;
 			break;

sys/sys/user.h

@@ -245,6 +245,7 @@ struct user {
 #define	KF_TYPE_KQUEUE	5
 #define	KF_TYPE_CRYPTO	6
 #define	KF_TYPE_MQUEUE	7
+#define	KF_TYPE_SHM	8
 #define	KF_TYPE_UNKNOWN	255
 
 #define	KF_VTYPE_VNON	0