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facebookincubator · Dec 14, 2024 · ce58686 · ce58686
1 parent 7c14239
commit ce58686
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/velox/common/file/FileInputStream.h b/velox/common/file/FileInputStream.h
@@ -55,6 +55,10 @@ class FileInputStream : public ByteInputStream {
 
   void readBytes(uint8_t* bytes, int32_t size) override;
 
+  /// Returns the view if required bytes keeps in the current file buffer,
+  /// otherwise, copy the bytes to IOBuf. Note: Not to readBytes until the
+  /// returned IOBuf is useless. You may overwrite the data in IOBuf if you read
+  /// more bytes.
   std::unique_ptr<folly::IOBuf> readBytes(int32_t size) override;
 
   std::string_view nextView(int32_t size) override;