diff --git a/examples/z_get_shm.c b/examples/z_get_shm.c
index 48ee8587b..c0846f6a4 100644
--- a/examples/z_get_shm.c
+++ b/examples/z_get_shm.c
@@ -67,7 +67,7 @@ int main(int argc, char** argv) {
     // Allocate SHM Buffer
     z_buf_layout_alloc_result_t alloc;
     z_shm_provider_alloc(&alloc, z_loan(provider), value_len, alignment);
-    if (!z_check(alloc.buf)) {
+    if (alloc.status != ZC_BUF_LAYOUT_ALLOC_STATUS_OK) {
         printf("Unexpected failure during SHM buffer allocation...");
         return -1;
     }
diff --git a/examples/z_ping_shm.c b/examples/z_ping_shm.c
index 085a617b0..5457def13 100644
--- a/examples/z_ping_shm.c
+++ b/examples/z_ping_shm.c
@@ -77,7 +77,7 @@ int main(int argc, char** argv) {
     // Allocate SHM Buffer
     z_buf_layout_alloc_result_t alloc;
     z_shm_provider_alloc(&alloc, z_loan(provider), args.size, alignment);
-    if (!z_check(alloc.buf)) {
+    if (alloc.status != ZC_BUF_LAYOUT_ALLOC_STATUS_OK) {
         printf("Unexpected failure during SHM buffer allocation...");
         return -1;
     }
diff --git a/examples/z_pub_shm.c b/examples/z_pub_shm.c
index 461816aca..cd259cceb 100644
--- a/examples/z_pub_shm.c
+++ b/examples/z_pub_shm.c
@@ -22,11 +22,22 @@
 #define DEFAULT_VALUE "Pub from C!"
 
 struct args_t {
-    char* keyexpr;  // -k
-    char* value;    // -v
+    char* keyexpr;               // -k
+    char* value;                 // -v
+    bool add_matching_listener;  // --add-matching-listener
 };
 struct args_t parse_args(int argc, char** argv, z_owned_config_t* config);
 
+#ifdef UNSTABLE
+void matching_status_handler(const zc_matching_status_t* matching_status, void* arg) {
+    if (matching_status->matching) {
+        printf("Subscriber matched\n");
+    } else {
+        printf("No Subscribers matched\n");
+    }
+}
+#endif
+
 int main(int argc, char** argv) {
     z_owned_config_t config;
     struct args_t args = parse_args(argc, argv, &config);
@@ -48,7 +59,7 @@ int main(int argc, char** argv) {
     }
 #ifdef UNSTABLE
     zc_owned_matching_listener_t listener;
-    if (add_matching_listener) {
+    if (args.add_matching_listener) {
         zc_owned_closure_matching_status_t callback;
         z_closure(&callback, matching_status_handler, NULL, NULL);
         zc_publisher_matching_listener_declare(&listener, z_loan(pub), z_move(callback));
@@ -76,7 +87,7 @@ int main(int argc, char** argv) {
 
         z_buf_layout_alloc_result_t alloc;
         z_shm_provider_alloc_gc_defrag_blocking(&alloc, z_loan(provider), buf_ok_size, alignment);
-        if (z_check(alloc.buf)) {
+        if (alloc.status == ZC_BUF_LAYOUT_ALLOC_STATUS_OK) {
             {
                 uint8_t* buf = z_shm_mut_data_mut(z_loan_mut(alloc.buf));
                 sprintf((char*)buf, "[%4d] %s", idx, args.value);
@@ -97,7 +108,7 @@ int main(int argc, char** argv) {
     }
 
 #ifdef UNSTABLE
-    if (add_matching_listener) {
+    if (args.add_matching_listener) {
         zc_publisher_matching_listener_undeclare(z_move(listener));
     }
 #endif
@@ -138,8 +149,13 @@ struct args_t parse_args(int argc, char** argv, z_owned_config_t* config) {
     if (!value) {
         value = DEFAULT_VALUE;
     }
+    const char* arg = parse_opt(argc, argv, "add-matching-listener", false);
+    bool add_matching_listener = false;
+    if (arg) {
+        add_matching_listener = true;
+    }
     parse_zenoh_common_args(argc, argv, config);
-    const char* arg = check_unknown_opts(argc, argv);
+    arg = check_unknown_opts(argc, argv);
     if (arg) {
         printf("Unknown option %s\n", arg);
         exit(-1);
@@ -151,5 +167,6 @@ struct args_t parse_args(int argc, char** argv, z_owned_config_t* config) {
         exit(-1);
     }
     free(pos_args);
-    return (struct args_t){.keyexpr = (char*)keyexpr, .value = (char*)value};
+    return (struct args_t){
+        .keyexpr = (char*)keyexpr, .value = (char*)value, .add_matching_listener = add_matching_listener};
 }
diff --git a/examples/z_pub_shm_thr.c b/examples/z_pub_shm_thr.c
index cc6d413a8..d91a18e46 100644
--- a/examples/z_pub_shm_thr.c
+++ b/examples/z_pub_shm_thr.c
@@ -66,7 +66,7 @@ int main(int argc, char **argv) {
     printf("Allocating single SHM buffer\n");
     z_buf_layout_alloc_result_t alloc;
     z_shm_provider_alloc(&alloc, z_loan(provider), len, alignment);
-    if (!z_check(alloc.buf)) {
+    if (alloc.status != ZC_BUF_LAYOUT_ALLOC_STATUS_OK) {
         printf("Unexpected failure during SHM buffer allocation...\n");
         return -1;
     }
diff --git a/examples/z_queryable_shm.c b/examples/z_queryable_shm.c
index e59eca281..1e4fab53f 100644
--- a/examples/z_queryable_shm.c
+++ b/examples/z_queryable_shm.c
@@ -51,7 +51,7 @@ void query_handler(const z_loaned_query_t *query, void *context) {
     z_alloc_alignment_t alignment = {0};
     z_buf_layout_alloc_result_t alloc;
     z_shm_provider_alloc_gc_defrag_blocking(&alloc, provider, value_len, alignment);
-    if (z_check(alloc.buf)) {
+    if (alloc.status == ZC_BUF_LAYOUT_ALLOC_STATUS_OK) {
         {
             uint8_t *buf = z_shm_mut_data_mut(z_loan_mut(alloc.buf));
             memcpy(buf, value, value_len);
diff --git a/include/zenoh_commons.h b/include/zenoh_commons.h
index 2af99424f..6aa2620b8 100644
--- a/include/zenoh_commons.h
+++ b/include/zenoh_commons.h
@@ -201,6 +201,50 @@ typedef enum z_whatami_t {
   Z_WHATAMI_PEER = 2,
   Z_WHATAMI_CLIENT = 4,
 } z_whatami_t;
+/**
+ * Status of SHM buffer allocation operation
+ */
+#if (defined(SHARED_MEMORY) && defined(UNSTABLE))
+typedef enum zc_buf_alloc_status_t {
+#if (defined(SHARED_MEMORY) && defined(UNSTABLE))
+  /**
+   * Allocation ok
+   */
+  ZC_BUF_ALLOC_STATUS_OK = 0,
+#endif
+#if (defined(SHARED_MEMORY) && defined(UNSTABLE))
+  /**
+   * Allocation error
+   */
+  ZC_BUF_ALLOC_STATUS_ALLOC_ERROR = 1,
+#endif
+} zc_buf_alloc_status_t;
+#endif
+/**
+ * Status of SHM buffer layouting + allocation operation
+ */
+#if (defined(SHARED_MEMORY) && defined(UNSTABLE))
+typedef enum zc_buf_layout_alloc_status_t {
+#if (defined(SHARED_MEMORY) && defined(UNSTABLE))
+  /**
+   * Allocation ok
+   */
+  ZC_BUF_LAYOUT_ALLOC_STATUS_OK = 0,
+#endif
+#if (defined(SHARED_MEMORY) && defined(UNSTABLE))
+  /**
+   * Allocation error
+   */
+  ZC_BUF_LAYOUT_ALLOC_STATUS_ALLOC_ERROR = 1,
+#endif
+#if (defined(SHARED_MEMORY) && defined(UNSTABLE))
+  /**
+   * Layouting error
+   */
+  ZC_BUF_LAYOUT_ALLOC_STATUS_LAYOUT_ERROR = 2,
+#endif
+} zc_buf_layout_alloc_status_t;
+#endif
 /**
  * The locality of samples to be received by subscribers or targeted by publishers.
  */
@@ -268,8 +312,12 @@ typedef enum zc_reply_keyexpr_t {
   ZC_REPLY_KEYEXPR_MATCHING_QUERY = 1,
 } zc_reply_keyexpr_t;
 #endif
+/**
+ * A result of SHM buffer allocation operation
+ */
 #if (defined(SHARED_MEMORY) && defined(UNSTABLE))
 typedef struct z_buf_alloc_result_t {
+  enum zc_buf_alloc_status_t status;
   z_owned_shm_mut_t buf;
   enum z_alloc_error_t error;
 } z_buf_alloc_result_t;
@@ -897,10 +945,13 @@ typedef struct zc_shm_client_callbacks_t {
   bool (*attach_fn)(struct z_shm_segment_t *out_segment, z_segment_id_t segment_id, void *context);
 } zc_shm_client_callbacks_t;
 #endif
+/**
+ * A result of SHM buffer layouting + allocation operation
+ */
 #if (defined(SHARED_MEMORY) && defined(UNSTABLE))
 typedef struct z_buf_layout_alloc_result_t {
+  enum zc_buf_layout_alloc_status_t status;
   z_owned_shm_mut_t buf;
-  bool error_is_alloc;
   enum z_alloc_error_t alloc_error;
   enum z_layout_error_t layout_error;
 } z_buf_layout_alloc_result_t;
diff --git a/splitguide.yaml b/splitguide.yaml
index c8cbae9f8..22bd854e5 100644
--- a/splitguide.yaml
+++ b/splitguide.yaml
@@ -86,6 +86,7 @@ zenoh_opaque.h:
   - z_owned_alloc_layout_t!#shared-memory#unstable
   - z_loaned_alloc_layout_t!#shared-memory#unstable
   - z_buf_alloc_result_t!#shared-memory#unstable
+  - zc_buf_alloc_status_t!#shared-memory#unstable
   - z_alloc_alignment_t!#shared-memory#unstable
   - z_chunk_descriptor_t!#shared-memory#unstable
   - z_allocated_chunk_t!#shared-memory#unstable
@@ -93,6 +94,7 @@ zenoh_opaque.h:
   - z_shm_segment_t!#shared-memory#unstable
   - zc_shm_client_callbacks_t!#shared-memory#unstable
   - z_buf_layout_alloc_result_t!#shared-memory#unstable
+  - zc_buf_layout_alloc_status_t!#shared-memory#unstable
   - zc_shm_provider_backend_callbacks_t!#shared-memory#unstable
   - z_layout_error_t!#shared-memory#unstable
   - z_alloc_error_t!#shared-memory#unstable
diff --git a/src/shm/provider/types.rs b/src/shm/provider/types.rs
index ae0b63c4f..a9c6cb9a5 100644
--- a/src/shm/provider/types.rs
+++ b/src/shm/provider/types.rs
@@ -249,8 +249,20 @@ pub extern "C" fn z_chunk_alloc_result_drop(this_: &mut z_moved_chunk_alloc_resu
     let _ = this_.take_rust_type();
 }
 
+/// Status of SHM buffer allocation operation
+#[repr(C)]
+#[derive(Clone, Copy, Debug)]
+pub enum zc_buf_alloc_status_t {
+    /// Allocation ok
+    OK = 0,
+    /// Allocation error
+    ALLOC_ERROR = 1,
+}
+
+/// A result of SHM buffer allocation operation
 #[repr(C)]
 pub struct z_buf_alloc_result_t {
+    status: zc_buf_alloc_status_t,
     buf: z_owned_shm_mut_t,
     error: z_alloc_error_t,
 }
@@ -262,6 +274,7 @@ impl From<BufAllocResult> for z_buf_alloc_result_t {
             Ok(val) => {
                 buf.as_rust_type_mut_uninit().write(Some(val));
                 Self {
+                    status: zc_buf_alloc_status_t::OK,
                     // SAFETY: this is safe because buf is gravestone-initialized above
                     buf: unsafe { buf.assume_init() },
                     error: z_alloc_error_t::OTHER,
@@ -270,6 +283,7 @@ impl From<BufAllocResult> for z_buf_alloc_result_t {
             Err(error) => {
                 z_internal_shm_mut_null(&mut buf);
                 Self {
+                    status: zc_buf_alloc_status_t::ALLOC_ERROR,
                     // SAFETY: this is safe because buf is gravestone-initialized above
                     buf: unsafe { buf.assume_init() },
                     error: error.into(),
@@ -279,10 +293,23 @@ impl From<BufAllocResult> for z_buf_alloc_result_t {
     }
 }
 
+/// Status of SHM buffer layouting + allocation operation
+#[repr(C)]
+#[derive(Clone, Copy, Debug)]
+pub enum zc_buf_layout_alloc_status_t {
+    /// Allocation ok
+    OK = 0,
+    /// Allocation error
+    ALLOC_ERROR = 1,
+    /// Layouting error
+    LAYOUT_ERROR = 2,
+}
+
+/// A result of SHM buffer layouting + allocation operation
 #[repr(C)]
 pub struct z_buf_layout_alloc_result_t {
+    status: zc_buf_layout_alloc_status_t,
     buf: z_owned_shm_mut_t,
-    error_is_alloc: bool,
     alloc_error: z_alloc_error_t,
     layout_error: z_layout_error_t,
 }
@@ -294,9 +321,9 @@ impl From<BufLayoutAllocResult> for z_buf_layout_alloc_result_t {
             Ok(val) => {
                 buf.as_rust_type_mut_uninit().write(Some(val));
                 Self {
-                    // SAFETY: this is safe because buf is gravestone-initialized above
+                    status: zc_buf_layout_alloc_status_t::OK,
+                    // SAFETY: this is safe because buf is initialized above
                     buf: unsafe { buf.assume_init() },
-                    error_is_alloc: false,
                     alloc_error: z_alloc_error_t::OTHER,
                     layout_error: z_layout_error_t::PROVIDER_INCOMPATIBLE_LAYOUT,
                 }
@@ -306,18 +333,18 @@ impl From<BufLayoutAllocResult> for z_buf_layout_alloc_result_t {
                 match error {
                     zenoh::shm::ZLayoutAllocError::Alloc(alloc) => {
                         Self {
+                            status: zc_buf_layout_alloc_status_t::ALLOC_ERROR,
                             // SAFETY: this is safe because buf is gravestone-initialized above
                             buf: unsafe { buf.assume_init() },
-                            error_is_alloc: true,
                             alloc_error: alloc.into(),
                             layout_error: z_layout_error_t::PROVIDER_INCOMPATIBLE_LAYOUT,
                         }
                     }
                     zenoh::shm::ZLayoutAllocError::Layout(layout) => {
                         Self {
+                            status: zc_buf_layout_alloc_status_t::LAYOUT_ERROR,
                             // SAFETY: this is safe because buf is gravestone-initialized above
                             buf: unsafe { buf.assume_init() },
-                            error_is_alloc: false,
                             alloc_error: z_alloc_error_t::OTHER,
                             layout_error: layout.into(),
                         }
diff --git a/tests/z_api_null_drop_test.c b/tests/z_api_null_drop_test.c
index 97cbe23eb..805f37f6b 100644
--- a/tests/z_api_null_drop_test.c
+++ b/tests/z_api_null_drop_test.c
@@ -54,7 +54,9 @@ int main(void) {
     TEST(closure_query)
     TEST(closure_reply)
     TEST(closure_hello)
+#ifdef UNSTABLE
     TEST(closure_zid)
+#endif
     TEST(string)
     TEST(string_array)
     TEST(sample)
diff --git a/tests/z_api_shm_test.c b/tests/z_api_shm_test.c
index 4f3267df9..d11b63eac 100644
--- a/tests/z_api_shm_test.c
+++ b/tests/z_api_shm_test.c
@@ -33,16 +33,16 @@
         return -300;      \
     }
 
-#define ASSERT_CHECK(var) \
-    if (!z_check(var)) {  \
-        assert(false);    \
-        return -100;      \
+#define ASSERT_CHECK(var)         \
+    if (!z_internal_check(var)) { \
+        assert(false);            \
+        return -100;              \
     }
 
-#define ASSERT_CHECK_ERR(var) \
-    if (z_check(var)) {       \
-        assert(false);        \
-        return -200;          \
+#define ASSERT_CHECK_ERR(var)    \
+    if (z_internal_check(var)) { \
+        assert(false);           \
+        return -200;             \
     }
 
 int test_shm_buffer(z_moved_shm_mut_t* mbuf) {
@@ -96,7 +96,8 @@ int test_layouted_allocation(const z_loaned_alloc_layout_t* alloc_layout) {
     z_alloc_error_t shm_error;
 
     z_alloc_layout_alloc_gc(&alloc, alloc_layout);
-    if (z_check(alloc.buf)) {
+    if (alloc.status == ZC_BUF_ALLOC_STATUS_OK) {
+        ASSERT_CHECK(alloc.buf);
         ASSERT_OK(test_shm_buffer(z_move(alloc.buf)));
         ASSERT_CHECK_ERR(alloc.buf);
         return Z_OK;
@@ -111,7 +112,8 @@ int test_allocation(const z_loaned_shm_provider_t* provider, size_t size, z_allo
     z_alloc_error_t shm_error;
 
     z_shm_provider_alloc_gc(&alloc, provider, size, alignment);
-    if (z_check(alloc.buf)) {
+    if (alloc.status == ZC_BUF_LAYOUT_ALLOC_STATUS_OK) {
+        ASSERT_CHECK(alloc.buf);
         ASSERT_OK(test_shm_buffer(z_move(alloc.buf)));
         ASSERT_CHECK_ERR(alloc.buf);
         return Z_OK;
@@ -244,7 +246,7 @@ void layout_for_fn(struct z_owned_memory_layout_t* layout, void* context) {
     assert(context);
     assert(layout);
 
-    assert(z_check(*layout));
+    assert(z_internal_check(*layout));
 
     // check size and alignment
     size_t size = 0;