what is meant by pragma once in c++

#pragma once

1. #pragma: This is a compiler directive in C++ that provides additional information to the compiler. It is not part of the C++ standard and is implementation-specific.

2. once: #pragma once is a specific directive used to ensure that the contents of a header file are included only once during the compilation of a program. It is a header guard mechanism to prevent multiple inclusions of the same file, which can lead to compilation errors due to redefinitions.

In summary, #pragma once is a preprocessor directive in C++ that is used to ensure that a header file is included only once in a translation unit, preventing issues related to multiple inclusions.