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diff --git a/fcp/tensorflow/file_descriptor_filesystem.h b/fcp/tensorflow/file_descriptor_filesystem.h
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+++ b/fcp/tensorflow/file_descriptor_filesystem.h
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+#ifndef FCP_TENSORFLOW_FILE_DESCRIPTOR_FILESYSTEM_H_
+#define FCP_TENSORFLOW_FILE_DESCRIPTOR_FILESYSTEM_H_
+
+#include <memory>
+#include <vector>
+
+#include "tensorflow/core/platform/file_system.h"
+
+namespace tensorflow {
+namespace fcp {
+
+// Filesystem for file descriptors that reads URIs in the form "fd:///<int>",
+// where <int> is a valid file descriptor number. This filesystem can be useful
+// to support situations in which a file descriptor is opened in Java and passed
+// to the JNI layer.
+//
+// CAVEATS:
+// * This filesystem is non-hierarchical and read-only; many functions simply
+//   return tensorflow::error::code::UNIMPLEMENTED.
+// * To read a file descriptor, this filesystem makes a dup and closes the dup
+//   when it is done with it. The code that originally created the URI is
+//   responsible for closing the original file descriptor.
+class FileDescriptorFileSystem : public tensorflow::FileSystem {
+ public:
+  FileDescriptorFileSystem() = default;
+  ~FileDescriptorFileSystem() override = default;
+
+  tensorflow::Status NewRandomAccessFile(
+      const std::string& filename,
+      std::unique_ptr<RandomAccessFile>* result) override;
+
+  // Clears *results and stores pattern if pattern is a literal match of a valid
+  // file descriptor. As such, this does not support the full pattern matching
+  // specification as described by FileSystem::GetMatchingPaths.
+  tensorflow::Status GetMatchingPaths(
+      const std::string& pattern, std::vector<std::string>* results) override;
+
+  tensorflow::Status Stat(const std::string& fname,
+                          tensorflow::FileStatistics* stats) override;
+
+  tensorflow::Status GetFileSize(const std::string& fname,
+                                 uint64* size) override;
+
+  // Not necessary to read TF checkpoints; these always return UNIMPLEMENTED
+  tensorflow::Status NewReadOnlyMemoryRegionFromFile(
+      const std::string& filename,
+      std::unique_ptr<ReadOnlyMemoryRegion>* result) override;
+
+  tensorflow::Status FileExists(const std::string& fname) override;
+
+  // The fd filesystem is non-hierarchical; this always returns UNIMPLEMENTED
+  tensorflow::Status GetChildren(const std::string& dir,
+                                 std::vector<string>* r) override;
+
+  // The fd filesystem is read-only; these always return UNIMPLEMENTED
+  tensorflow::Status NewWritableFile(
+      const std::string& fname, std::unique_ptr<WritableFile>* result) override;
+  tensorflow::Status NewAppendableFile(
+      const std::string& fname, std::unique_ptr<WritableFile>* result) override;
+  tensorflow::Status DeleteFile(const std::string& f) override;
+  tensorflow::Status CreateDir(const std::string& d) override;
+  tensorflow::Status DeleteDir(const std::string& d) override;
+  tensorflow::Status RenameFile(const std::string& s,
+                                const std::string& t) override;
+  tensorflow::Status CanCreateTempFile(const std::string& fname,
+                                       bool* can_create_temp_file) override;
+};
+
+}  // namespace fcp
+}  // namespace tensorflow
+
+#endif  // FCP_TENSORFLOW_FILE_DESCRIPTOR_FILESYSTEM_H_