diff --git a/programs/include/montauk/statuscodes.h b/programs/include/montauk/statuscodes.h
index a078ea0..2f94f00 100644
--- a/programs/include/montauk/statuscodes.h
+++ b/programs/include/montauk/statuscodes.h
@@ -60,6 +60,13 @@ inline const char* GetStatusText(StatusCode statusCode) {
     }
 }
 
+// Map a raw syscall result to a StatusCode.
+inline StatusCode StatusFromResult(long long rc) {
+    if (rc >= 0) return Success;
+    if (rc < -(long long)WouldBlock) return GenericFailure;
+    return (StatusCode)(-rc);
+}
+
 // Shared with C (libc.c), so no nullptr.
 inline const char* GetStatusExplanationText(StatusCode statusCode) {
     const char* explanationText[] = {
diff --git a/programs/lib/libc/libc.c b/programs/lib/libc/libc.c
index a3bbc03..44d8207 100644
--- a/programs/lib/libc/libc.c
+++ b/programs/lib/libc/libc.c
@@ -2494,7 +2494,7 @@ char *getcwd(char *buf, size_t size) {
     }
     int result = (int)_mtk_syscall2(SYS_GETCWD, (long)buf, (long)size);
     if (result < 0) {
-        errno = result == BufferTooSmall ? ERANGE : EIO;
+        errno = result == -BufferTooSmall ? ERANGE : EIO;
         return NULL;
     }
     return buf;
@@ -3584,10 +3584,11 @@ int utime(const char *path, const struct utimbuf *times) {
                                 times != NULL ? (long)times->modtime : 0,
                                 times == NULL);
     if (result == 0) return 0;
-    if (result == UnsupportedOp) errno = ENOTSUP;
-    else if (result == InvalidArgument) errno = EOVERFLOW;
-    else if (result == IoFailure) errno = EIO;
-    else if (result == SystemIntegrityError) errno = EPERM;
+    /* The kernel returns StatusCodes negated. */
+    if (result == -UnsupportedOp) errno = ENOTSUP;
+    else if (result == -InvalidArgument) errno = EOVERFLOW;
+    else if (result == -IoFailure) errno = EIO;
+    else if (result == -SystemIntegrityError) errno = EPERM;
     else errno = ENOENT;
     return -1;
 }
diff --git a/programs/src/desktop/apps/filemanager/filemanager_internal.hpp b/programs/src/desktop/apps/filemanager/filemanager_internal.hpp
index ba700a2..848f6df 100644
--- a/programs/src/desktop/apps/filemanager/filemanager_internal.hpp
+++ b/programs/src/desktop/apps/filemanager/filemanager_internal.hpp
@@ -234,10 +234,7 @@ void filemanager_read_system_configuration(FileManagerState* fm);
 // Map a raw syscall result (kernel StatusCodes are negative) to a userspace
 // montauk::StatusCodes. Non-negative results (handles, counts) are Success.
 inline montauk::StatusCode filemanager_status_from_result(int rc) {
-    if (rc >= 0) return montauk::Success;
-    int code = -rc;
-    if (code > montauk::OutOfMemory) return montauk::GenericFailure;
-    return (montauk::StatusCode)code;
+    return montauk::StatusFromResult(rc);
 }
 
 // The path itself may not be modified. Falling back to copy + delete after a
diff --git a/programs/src/display/main.cpp b/programs/src/display/main.cpp
index 77455b2..d6b0653 100644
--- a/programs/src/display/main.cpp
+++ b/programs/src/display/main.cpp
@@ -501,7 +501,7 @@ static void apply_changes() {
     if (g_driver_available && g_selected_mode != g_info.currentMode) {
         int result = montauk::display_set_mode(g_selected_mode);
         if (result < 0) {
-            set_status(result == montauk::UnsupportedOp
+            set_status(montauk::StatusFromResult(result) == montauk::UnsupportedOp
                 ? "Mode needs unsupported display-link training"
                 : "Mode change failed; previous mode restored");
             refresh_state(true);
diff --git a/programs/src/login/login_shutdown.cpp b/programs/src/login/login_shutdown.cpp
index bf0dcdd..36308e0 100644
--- a/programs/src/login/login_shutdown.cpp
+++ b/programs/src/login/login_shutdown.cpp
@@ -262,7 +262,7 @@ void perform_graceful_shutdown(LoginState* ls, int action) {
     // A successful power-control syscall never returns.  If it does return,
     // keep the trusted supervisor alive and make the authorization failure
     // visible instead of falling through an unreachable-code assumption.
-    show_stage(ls, heading, rc == montauk::CapabilityDenied
+    show_stage(ls, heading, montauk::StatusFromResult(rc) == montauk::CapabilityDenied
         ? "Power control permission denied."
         : "Power control failed.");
     for (;;) montauk::sleep_ms(1000);
diff --git a/programs/src/reset/main.cpp b/programs/src/reset/main.cpp
index 9f0bde7..b4278e4 100644
--- a/programs/src/reset/main.cpp
+++ b/programs/src/reset/main.cpp
@@ -9,7 +9,7 @@
 extern "C" void _start() {
     montauk::print("Rebooting...\n");
     int rc = montauk::reset();
-    if (rc == montauk::CapabilityDenied)
+    if (montauk::StatusFromResult(rc) == montauk::CapabilityDenied)
         montauk::print("reset: permission denied\n");
     else
         montauk::print("reset: reboot failed\n");
diff --git a/programs/src/shell/main.cpp b/programs/src/shell/main.cpp
index 1ef09e5..2b19f77 100644
--- a/programs/src/shell/main.cpp
+++ b/programs/src/shell/main.cpp
@@ -196,7 +196,7 @@ static int process_command(const char* line) {
             : montauk::abi::POWER_REQ_SHUTDOWN;
         int rc = montauk::power_request(action);
         if (rc == 0) montauk::exit(0);
-        montauk::print(rc == montauk::CapabilityDenied
+        montauk::print(montauk::StatusFromResult(rc) == montauk::CapabilityDenied
             ? "power: permission denied\n"
             : "power: request failed\n");
         return 1;
@@ -204,7 +204,7 @@ static int process_command(const char* line) {
 
     if (streq(cmd, "suspend")) {
         int rc = montauk::suspend();
-        if (rc == montauk::CapabilityDenied)
+        if (montauk::StatusFromResult(rc) == montauk::CapabilityDenied)
             montauk::print("suspend: permission denied\n");
         return rc == 0 ? 0 : 1;
     }