What is value of EOF and '\0' in C

c++ c null eof
theReverseFlick picture theReverseFlick · Jan 16, 2011 · Viewed 91.2k times · Source

I know that EOF and '\0' 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 '\0'. But are these values fixed?

I also had this

int a=-1;

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

Are the value for EOF and '\0' fixed integers?

Answer

CB Bailey picture CB Bailey · Jan 16, 2011

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.

'\0' 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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