diff --git a/copyparty/__init__.py b/copyparty/__init__.py
index afb05d18..c844853d 100644
--- a/copyparty/__init__.py
+++ b/copyparty/__init__.py
@@ -44,6 +44,8 @@ ANYWIN = WINDOWS or sys.platform in ["msys", "cygwin"]
 
 MACOS = platform.system() == "Darwin"
 
+GRAAL = platform.python_implementation() == "GraalVM"
+
 EXE = bool(getattr(sys, "frozen", False))
 
 try:
diff --git a/copyparty/stolen/ifaddr/__init__.py b/copyparty/stolen/ifaddr/__init__.py
index 5e8b7827..1ea51e2b 100644
--- a/copyparty/stolen/ifaddr/__init__.py
+++ b/copyparty/stolen/ifaddr/__init__.py
@@ -8,6 +8,7 @@ https://github.com/pydron/ifaddr/tree/0.2.0
 """
 
 import os
+import platform
 
 from ._shared import IP, Adapter
 
@@ -16,20 +17,28 @@ def nope(include_unconfigured=False):
     return []
 
 
-try:
-    S390X = os.uname().machine == "s390x"
-except:
-    S390X = False
+host_os = platform.system()
+machine = platform.machine()
+py_impl = platform.python_implementation()
 
 
-if os.environ.get("PRTY_NO_IFADDR") or S390X:
+if os.environ.get("PRTY_NO_IFADDR"):
+    get_adapters = nope
+elif machine in ("s390x",) or host_os in ("IRIX32",):
     # s390x deadlocks at libc.getifaddrs
+    # irix libc does not have getifaddrs at all
+    print("ifaddr unavailable; can't determine LAN IP: unsupported OS")
+    get_adapters = nope
+elif py_impl in ("GraalVM",):
+    print("ifaddr unavailable; can't determine LAN IP: unsupported interpreter")
     get_adapters = nope
 elif os.name == "nt":
     from ._win32 import get_adapters
 elif os.name == "posix":
     from ._posix import get_adapters
 else:
-    raise RuntimeError("Unsupported Operating System: %s" % os.name)
+    print("ifaddr unavailable; can't determine LAN IP: unsupported OS")
+    get_adapters = nope
+
 
 __all__ = ["Adapter", "IP", "get_adapters"]
diff --git a/copyparty/util.py b/copyparty/util.py
index 1b9b5431..52a16519 100644
--- a/copyparty/util.py
+++ b/copyparty/util.py
@@ -45,6 +45,7 @@ except:
 from .__init__ import (
     ANYWIN,
     EXE,
+    GRAAL,
     MACOS,
     PY2,
     PY36,
@@ -56,6 +57,11 @@ from .__init__ import (
 )
 from .__version__ import S_BUILD_DT, S_VERSION
 
+
+def noop(*a, **ka):
+    pass
+
+
 try:
     from datetime import datetime, timezone
 
@@ -280,6 +286,9 @@ except:
     BITNESS = struct.calcsize("P") * 8
 
 
+CAN_SIGMASK = not (ANYWIN or PY2 or GRAAL)
+
+
 RE_ANSI = re.compile("\033\\[[^mK]*[mK]")
 RE_HTML_SH = re.compile(r"[<>&$?`\"';]")
 RE_CTYPE = re.compile(r"^content-type: *([^; ]+)", re.IGNORECASE)
@@ -779,7 +788,7 @@ class Daemon(threading.Thread):
             self.start()
 
     def run(self):
-        if not ANYWIN and not PY2:
+        if CAN_SIGMASK:
             signal.pthread_sigmask(
                 signal.SIG_BLOCK, [signal.SIGINT, signal.SIGTERM, signal.SIGUSR1]
             )
@@ -1655,15 +1664,15 @@ def log_thrs(log: Callable[[str, str, int], None], ival: float, name: str) -> No
         log(name, "\033[0m \033[33m".join(tv), 3)
 
 
-def sigblock():
-    if ANYWIN or PY2:
-        return
-
+def _sigblock():
     signal.pthread_sigmask(
         signal.SIG_BLOCK, [signal.SIGINT, signal.SIGTERM, signal.SIGUSR1]
     )
 
 
+sigblock = _sigblock if CAN_SIGMASK else noop
+
+
 def vol_san(vols: list["VFS"], txt: bytes) -> bytes:
     txt0 = txt
     for vol in vols: