What is the means of ( __ ) "double underscore" used in c like , ie: __asm__ Every where I found that they are reserved for compiler . But Actually what it means and how we or compiler use them, It would be better if sombody explain with use case.
We know it is reserved but how compiler interprets these symbols for specific purpose.
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sepp2k
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Rahul Verma
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The implementation may define any number of symbols (function names, variable names, macros, etc.) for internal use. To avoid collisions with user-defined symbols, certain naming patterns are reserved for these internal symbols, such as leading __.
IOW, if you name a variable __foo__, you run the risk of a compile-time or link-time error if the implementation has already defined __foo__ for a different purpose.
Apart from that, they have no special meaning.
John Bode
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