From: Bob Stout 

On Mon, 12 Jan 2004, prabir senapati wrote:

> Can anyone explain me, how and why sometimes in API's or user defined
> functions, we use to declare (store) a character in an int data type, or
> in other words , store a char variable in an int storage ??
>
> Many C API's like int getc(FILE *fp) , int putc(int c, FILE *fp).....
> uses this concept, as return type of getc is char as explained in
> books(K&R) but declared as int , again the param c in putc is char but
> defined as int.. Can't we declare them as char instead of int ? How and
> why is this ?? Any one Please explain me or point me to good references.

Simple... Most of the character functions (e.g. getc()) have to return an
int in order to be able to return an error condition - typically -1. If it
returned a char, -1 would simply be 0xff which is a legal character. By
returning an int, an error is unambiguously larger than a character.

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