Need to close file descriptor

pyop2/caching.py

@@ -324,12 +324,14 @@ def __setitem__(self, key, value):
         # the filesystem may be network based. `mkstemp` does so securely without
         # race conditions:
         # https://docs.python.org/3/library/tempfile.html#tempfile.mkstemp
-        _, tempfile = mkstemp(suffix=".tmp", prefix=k2, dir=basedir, text=False)
+        # The file descriptor must also be closed after use with `os.close()`.
+        fd, tempfile = mkstemp(suffix=".tmp", prefix=k2, dir=basedir, text=False)
         tempfile = Path(tempfile)
         # Open using `tempfile` (the filename) rather than the file descriptor
         # to allow redefining `self.open`
         with self.open(tempfile, mode="wb") as fh:
             self.write(fh, value)
+        os.close(fd)
 
         # Renaming (moving) the file is guaranteed by any POSIX compliant
         # filesystem to be atomic. This may fail if somehow the destination is

pyop2/compilation.py

@@ -595,7 +595,7 @@ def make_so(compiler, jitmodule, extension, comm, filename=None):
             tempdir = MEM_TMP_DIR.joinpath(f"{randint(0, 255):02x}")
             tempdir.mkdir(parents=True, exist_ok=True)
             # This path + filename should be unique
-            _, filename = mkstemp(suffix=f".{extension}", dir=tempdir, text=True)
+            descriptor, filename = mkstemp(suffix=f".{extension}", dir=tempdir, text=True)
             filename = Path(filename)
         else:
             filename.parent.mkdir(exist_ok=True)
@@ -609,6 +609,7 @@ def make_so(compiler, jitmodule, extension, comm, filename=None):
             # Write source code to disk
             with open(cname, "w") as fh:
                 fh.write(jitmodule.code_to_compile)
+            os.close(descriptor)
 
             if not compiler.ld:
                 # Compile and link