3dl-dev · baron-3dl · Aug 13, 2026 · Aug 13, 2026 · Aug 13, 2026 · Aug 13, 2026
diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -575,6 +575,18 @@ if(BUILD_TESTS)
     set_tests_properties(show_device_rows_negctl PROPERTIES
         LABELS "integration;authenticity" TIMEOUT 300)
 
+    # SHOW CLUSTER reflects the SCS daemon's LIVE membership (rd vms-8d4,
+    # INV-DCL). cmd_show_cluster() used to hardcode %SYSTEM-I-NOTMEMBER, so a
+    # genuinely-clustered node lied. This RUNS DCL against a membership file
+    # written in SCSD's own publication format (scs_membership.h -- the real
+    # boundary between the daemon and the DCL process) and requires the member
+    # set to be shown when present and NOTMEMBER only when genuinely absent.
+    add_test(NAME show_cluster_membership_gate
+        COMMAND ${CMAKE_CURRENT_SOURCE_DIR}/tests/integration/test_show_cluster_membership.sh
+                $<TARGET_FILE:vmsdcl>)
+    set_tests_properties(show_cluster_membership_gate PROPERTIES
+        LABELS "integration;authenticity;cluster" TIMEOUT 60)
+
     # SHOW SYMBOL renders an integer's Hex and Octal columns as a LONGWORD
     # (rd vms-c71), pinned to a side-by-side measurement against OpenVMS VAX
     # V7.3. Two defects lived on one line: a negative sign-extended to 16 hex

diff --git a/src/imgact/test/run_dcl_native.sh b/src/imgact/test/run_dcl_native.sh
@@ -85,7 +85,7 @@ CFLAGS="-fPIC -O2 -ffreestanding -fno-builtin -fno-stack-protector -U_FORTIFY_SO
 DEFS="-D_POSIX_C_SOURCE=200809L -D_DEFAULT_SOURCE"
 # -I$LIBVMSSYS_DIR (vms-8019): dcl_cmd_show.c includes "vms_kif.h" — SHOW SYSTEM
 # reads the executive's process table through vms_kif_procscan().
-INCS="-I$DCL_DIR/include -I$LIBVMS_INC -I$VMSFS_INC -I$LNM_INC -I$RMS_INC -I$VMSPROC_DIR/include -I$SRC/vmsqueue -I$LIBVMSSYS_DIR"
+INCS="-I$DCL_DIR/include -I$LIBVMS_INC -I$VMSFS_INC -I$LNM_INC -I$RMS_INC -I$VMSPROC_DIR/include -I$SRC/vmsqueue -I$LIBVMSSYS_DIR -I$SRC/vmsscs/include"
 TUS="dcl_main dcl_lexer dcl_parser dcl_exec dcl_backup dcl_builtin dcl_cmd_show \
 dcl_cmd_set dcl_cmd_file dcl_cmd_process dcl_cmd_io dcl_cmd_misc dcl_disk_logical \
 dcl_editor dcl_terminal dcl_symbol dcl_lexical dcl_filespec dcl_io dcl_script \

diff --git a/src/libvms/CMakeLists.txt b/src/libvms/CMakeLists.txt
@@ -63,6 +63,9 @@ target_include_directories(vms PUBLIC include ${VMS_RMS_INCLUDE_DIR} ${VMS_FS_IN
 # (ovmx_image.h / ovmx_symvec.h) -- the same single-source-of-truth headers
 # LINK.EXE and IMGACT.EXE share (vms-db2). PRIVATE: only these TUs need them.
 target_include_directories(vms PRIVATE ${CMAKE_SOURCE_DIR}/src/vmslink/include)
+# F$GETSYI CLUSTER_MEMBER/CLUSTER_NODES read SCSD's live membership publication
+# (vms-8d4): src/vmsscs/include/scs_membership.h -- header-only, no link dep.
+target_include_directories(vms PRIVATE ${CMAKE_SOURCE_DIR}/src/vmsscs/include)
 # vmssys provides vms_kif_* (the /dev/vms ioctl wrappers used by sys_lock.c
 # to reach the kernel lock manager).
 target_link_libraries(vms PUBLIC vmsprocess vmsfs vmssys pthread m)

diff --git a/src/libvms/syssvc/sys_misc.c b/src/libvms/syssvc/sys_misc.c
@@ -40,6 +40,7 @@
 #include "sysgen_params.h"
 #include "ovmx_identity.h"
 #include "vms_kif.h"        /* the executive OWNS privilege state (vms-pv1) */
+#include "scs_membership.h" /* vms-8d4: live cluster membership from SCSD */
 
 /*
  * sys$setprv - Set or clear process privileges.
@@ -214,19 +215,30 @@ uint32_t sys$getsyi(uint32_t efn, const uint32_t *csidadr,
             }
 
             case SYI$_CLUSTER_MEMBER: {
-                uint32_t vaxcluster = 0;   /* OVMX default: not cluster-enabled */
-                (void)sysgen_read_param("VAXCLUSTER", &vaxcluster);
-                uint32_t member = (vaxcluster != 0) ? 1 : 0;
+                /* vms-8d4: the LIVE fact, read from SCSD's published member set
+                 * (scs_membership.h) — not the static SYSGEN VAXCLUSTER config
+                 * flag, which said "member" whenever clustering was enabled even
+                 * with no cluster formed. A node is a member iff the connection
+                 * manager has admitted it into a cluster (>=1 published member).
+                 * This keeps F$GETSYI consistent with DCL SHOW CLUSTER. */
+                struct scs_cluster_view view;
+                uint32_t member =
+                    (scs_membership_read(&view) > 0 && view.n_members >= 1)
+                        ? 1 : 0;
                 if (item->bufaddr && item->buflen >= sizeof(uint32_t))
                     *(uint32_t *)item->bufaddr = member;
                 if (item->retlen) *item->retlen = sizeof(uint32_t);
                 break;
             }
 
             case SYI$_CLUSTER_NODES: {
-                /* OVMX has no live cluster wire yet (vms-ci.3) — report
-                 * this node only. */
-                uint32_t nodes = 1;
+                /* vms-8d4: live cluster node count from SCSD's published member
+                 * set; 1 (this node only) when not a member. Was hardcoded to
+                 * 1 unconditionally (vms-ci.3), which lied on a real cluster. */
+                struct scs_cluster_view view;
+                uint32_t nodes =
+                    (scs_membership_read(&view) > 0 && view.n_members >= 1)
+                        ? (uint32_t)view.n_members : 1;
                 if (item->bufaddr && item->buflen >= sizeof(uint32_t))
                     *(uint32_t *)item->bufaddr = nodes;
                 if (item->retlen) *item->retlen = sizeof(uint32_t);

diff --git a/src/vmsdcl/CMakeLists.txt b/src/vmsdcl/CMakeLists.txt
@@ -37,6 +37,10 @@ target_include_directories(vmsdcl PRIVATE
     # kernel-interface client (vms-fb9): src/libvmssys/vms_kif.h, which
     # pulls src/kernel/vms_ioctl.h for the shared ioctl structures.
     ${CMAKE_SOURCE_DIR}/src/libvmssys
+    # SHOW CLUSTER reads the SCS daemon's live membership publication
+    # (vms-8d4): src/vmsscs/include/scs_membership.h -- a header-only IPC,
+    # so no vmsscs link dependency is added.
+    ${CMAKE_SOURCE_DIR}/src/vmsscs/include
 )
 
 # We need POSIX APIs (fork, sigaction, strncasecmp, realpath, etc.)

diff --git a/src/vmsdcl/dcl_cmd_show.c b/src/vmsdcl/dcl_cmd_show.c
@@ -37,6 +37,7 @@
 #include "vms/pcb.h"
 #include "ovmx_identity.h"
 #include "ovmx_accounting.h"
+#include "scs_membership.h"  /* vms-8d4: read SCSD's live cluster membership */
 #include "vmsqueue.h"
 #include "descrip.h"
 #include "jpidef.h"
@@ -2379,11 +2380,78 @@ static int cmd_show_license(struct dcl_command *cmd)
 
 /*
  * SHOW CLUSTER - Display VMScluster membership.
+ *
+ * vms-8d4 (INV-DCL facade-kill): this used to hardcode "%SYSTEM-I-NOTMEMBER"
+ * unconditionally, so a genuinely-clustered node lied about being standalone.
+ * It now reads the connection manager's LIVE member set, published by the SCS
+ * daemon (src/vmsscs/scsd.c -> scs_membership.h). When the daemon has admitted
+ * this node into a cluster it renders the real member list; when this node is
+ * not a member -- daemon not running, or not (yet) joined -- there is no
+ * published membership and NOTMEMBER is the honest answer, exactly as a real
+ * non-member VMS node reports.
+ *
+ * The display fields (the "View of Cluster from system ID N node: X" banner and
+ * the NODE / SOFTWARE / STATUS columns) are modeled on the public OpenVMS SHOW
+ * CLUSTER utility default report (Rule 8: matched to documented output, not to
+ * any VMS binary). The line art is an OVMX rendering.
  */
 static int cmd_show_cluster(struct dcl_command *cmd)
 {
     (void)cmd;
-    printf("%%SYSTEM-I-NOTMEMBER, this system is not a member of a VMScluster\n");
+
+    struct scs_cluster_view view;
+    int rc = scs_membership_read(&view);
+
+    if (rc <= 0 || view.n_members < 1) {
+        /* Not a member: no live membership published. This is the truth for a
+         * standalone node and for a node whose connection manager is not up. */
+        printf("%%SYSTEM-I-NOTMEMBER, this system is not a member of a "
+               "VMScluster\n");
+        return SS$_NORMAL;
+    }
+
+    /* members[0] is the local node, as published by SCSD. */
+    const struct scs_cluster_member *local = &view.members[0];
+    const char *local_node =
+        (local->node[0] != '\0' && strcmp(local->node, "?") != 0)
+            ? local->node : "OVMX";
+
+    char tbuf[64];
+    time_t now = time(NULL);
+    struct tm tmv;
+    localtime_r(&now, &tmv);
+    /* VMS date form: dd-MON-yyyy hh:mm:ss (month letters uppercased). */
+    strftime(tbuf, sizeof(tbuf), "%d-%b-%Y %H:%M:%S", &tmv);
+    for (char *p = tbuf; *p; p++) *p = (char)toupper((unsigned char)*p);
+
+    /* We know only THIS node's software version; the membership publication
+     * carries no per-peer software, so peer rows show the family ("VMS")
+     * without a version we cannot vouch for (Rule 8 / INV-DCL: never state a
+     * fact we did not observe). */
+    char local_software[24];
+    snprintf(local_software, sizeof(local_software), "VMS %s",
+             ovmx_compat_version());
+
+    printf("View of Cluster from system ID %u node: %-6s   %s\n\n",
+           (unsigned)local->sysid, local_node, tbuf);
+    printf("+-------------------------------------------------+\n");
+    printf("|          SYSTEMS         |       MEMBERS         |\n");
+    printf("|--------------------------+----------------------|\n");
+    printf("| NODE   | SOFTWARE        | STATUS               |\n");
+    printf("|--------+-----------------+----------------------|\n");
+    for (int i = 0; i < view.n_members; i++) {
+        const struct scs_cluster_member *m = &view.members[i];
+        char nodecol[SCS_MEMBERSHIP_NODE_LEN];
+        if (m->node[0] != '\0' && strcmp(m->node, "?") != 0) {
+            snprintf(nodecol, sizeof(nodecol), "%s", m->node);
+        } else {
+            /* Peer SCSNODE name not learned: identify it by SCSSYSTEMID. */
+            snprintf(nodecol, sizeof(nodecol), "%u", (unsigned)m->sysid);
+        }
+        const char *software = (i == 0) ? local_software : "VMS";
+        printf("| %-6s | %-15s | %-20s |\n", nodecol, software, m->state);
+    }
+    printf("+-------------------------------------------------+\n");
     return SS$_NORMAL;
 }
 

diff --git a/src/vmslink/mk_dcl.sh b/src/vmslink/mk_dcl.sh
@@ -105,7 +105,8 @@ CFLAGS="${CFLAGS:--fPIC -O2 -ffreestanding -fno-builtin -fno-stack-protector -mn
 DEFS="-D_POSIX_C_SOURCE=200809L -D_DEFAULT_SOURCE"
 INCS="-I$DCL/include -I$REPO_SRC/libvms/include -I$REPO_SRC/vmsfs/include \
 -I$REPO_SRC/vmslnm/include -I$REPO_SRC/vmsrms/include \
--I$REPO_SRC/vmsprocess/include -I$REPO_SRC/vmsqueue -I$REPO_SRC/libvmssys"
+-I$REPO_SRC/vmsprocess/include -I$REPO_SRC/vmsqueue -I$REPO_SRC/libvmssys \
+-I$REPO_SRC/vmsscs/include"   # scs_membership.h for SHOW CLUSTER (vms-8d4)
 
 # The 22 vmsdcl TUs (== src/vmsdcl/CMakeLists.txt, minus readline convenience).
 TUS="dcl_main dcl_lexer dcl_parser dcl_exec dcl_backup dcl_builtin dcl_cmd_show \

diff --git a/src/vmslink/mk_decc_shr.sh b/src/vmslink/mk_decc_shr.sh
@@ -348,6 +348,7 @@ inet_ntop=PROCEDURE,inet_pton=PROCEDURE,ioctl=PROCEDURE,isatty=PROCEDURE,\
 isxdigit=PROCEDURE,mktime=PROCEDURE,ntohl=PROCEDURE,pipe=PROCEDURE,\
 readlink=PROCEDURE,rewind=PROCEDURE,setrlimit=PROCEDURE,settimeofday=PROCEDURE,\
 sleep=PROCEDURE,socket=PROCEDURE,strerror=PROCEDURE,strptime=PROCEDURE,\
+strftime=PROCEDURE,\
 system=PROCEDURE,tcgetattr=PROCEDURE,tcsetattr=PROCEDURE,utimes=PROCEDURE,\
 \
 __addtf3=PROCEDURE,__divtf3=PROCEDURE,__eqtf2=PROCEDURE,__extenddftf2=PROCEDURE,\

diff --git a/src/vmslink/mk_libvms_shr.sh b/src/vmslink/mk_libvms_shr.sh
@@ -83,7 +83,9 @@ CFLAGS="${CFLAGS:--fPIC -O2 -ffreestanding -fno-builtin -fno-stack-protector -mn
 INCS="-I$SRC/include -I$HERE/../libvmssys \
 -I$HERE/../vmsprocess/include -I$HERE/../vmslnm/include \
 -I$HERE/../vmsfs/include -I$HERE/../vmsrms/include \
+-I$HERE/../vmsscs/include \
 -I$HERE/include"   # ovmx_image.h/ovmx_symvec.h for sys_imgact + imgact_prodreg (vms-db2)
+                   # vmsscs/include: scs_membership.h for F$GETSYI CLUSTER_* (vms-8d4)
 
 echo "mk_libvms_shr: LINK.EXE=$LINK_EXE  CC=$CC  GSMATCH=$GSMATCH"
 echo "mk_libvms_shr: src=$SRC"