diff -r 0acc5626a578 Modules/faulthandler.c
@@ -445,7 +445,10 @@
-        write(thread.fd, thread.header, thread.header_len);
+        if (write(thread.fd, thread.header, thread.header_len) == -1) {
+            PyErr_SetFromErrno(PyExc_IOError);
+            return; 
+        }
 
I wrote faulthandler to debug deadlocks, memory corruptions and other cases where Python internals are no consistency anymore.

faulthandler_thread() is not a Python thread, but a C thread. I don't know if it's legal to call PyErr_SetFromErrno(). And it would be really surprising to get a Python exception whereas it does not come from Python code.

I would prefer to just ignore if write() failed here.