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c++ - What is value of EOF and '' in C

I know that EOF and '' are of type integers, but if so shouldn't they have a fixed value?

I printed both and got -1 for EOF and 0 for ''. But are these values fixed?

I also had this

int a=-1;

printf("%d",a==EOF); //printed 1

Are the value for EOF and '' fixed integers?

question from:https://stackoverflow.com/questions/4705968/what-is-value-of-eof-and-0-in-c

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EOF is a macro which expands to an integer constant expression with type int and an implementation dependent negative value but is very commonly -1.

'' is a char with value 0 in C++ and an int with the value 0 in C.

The reason why printf("%d",a==EOF); resulted in 1 was because you didn't assign the value EOF to a. Instead you checked if a was equal to EOF and since that was true (a == -1 == EOF) it printed 1.


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