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Why must the variable used to hold getchar's return value be declared as int?

I am beginner in C programming language, recently I have studied about getchar function, which will accept a character from the console or from a file, display it immediately while typing and we need to press Enter key for proceeding.

It returns the unsigned char that they read. If end-of-file or an error is encountered getchar() functions return EOF.

My question is that, When it returns unsigned char, then why its returned value is stored in int variable?

Please help me.

Solution

  • Precisely because of that EOF-value. Because a char in a file may be any possible char value, including the null character that C-strings use for termination, getchar() must use a larger integer type to add an EOF-value.

    It simply happens to use int for that purpose, but it could use any type with at least 9 bit.