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header-guard [May 14, 2026 at 12:59] – yanevskivheader-guard [May 14, 2026 at 13:01] (current) – yanevskiv
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 # Header guard # Header guard
-**Header guards** are a pattern used in C and C++ programming languages when writing header files. Header files (.h files) are files that are included in source files (.c and .cpp files) using the `#include <...>` directive. They are used to allow multiple inclusions of the same file but prevent multiple definition errors. +**Header guards** are a pattern used in C and C++ programming languages when writing header files. Header files (.h files) are files that are included in source files (.c and .cpp files) near the top (hence the name) using the `#include <...>` directive. They are used to allow multiple inclusions of the same file but prevent multiple definition errors. 
  
-Header guards follow the same general pattern. +Header guards follow the same general pattern:
 ```c ```c
 #ifndef __HEADER_GUARD_H__ #ifndef __HEADER_GUARD_H__
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 // ... // ...
  
-#endif+#endif /* __HEADER_GUARD_H__ (This is just a comment) */
 ``` ```
  
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 ``` ```
  
-### Why?+This allows multiple inclusion of "hello\_world.h"
 ```c ```c
 // main.c // main.c
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 } }
 ``` ```
 +
header-guard.1778763550.txt.gz · Last modified: by yanevskiv