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Re: potential runtime problem on arm, powerpc and s390 due to incorrect assumption on char signedness

Previously Gerhard Tonn wrote:
> >>The following code fragment will ignore the end-of-file when char is 
> >>implemented using unsigned char, due to internal conversions between data
> >>types:
> >>
> >>                char c;
> >>                while ((c = getchar()) != EOF)
> >>                      process character in c

> In other contexts the right solution is to make the type of the variable 
> 'signed char'.

No, the right solution here is make c of type `int'. getchar() does
not return a char for a very obvious reason: if it did one would not
be able to distinguish between a valid character read from the keyboard
and an error condition.


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