problem with Data Files

[CBFalconer]

The C Standard has always required it to be sticky. Some (perhaps
even many) implementations still get it wrong.

On stdin from the keyboard? On disk files I agree.

 

[Adrianp]

If you want to know the value of EOF on your compiler look in stdio.h (or
whatever io lib you are using). eg

#define EOF (-1)

Try this program: EOF is always -1,

It might be for a given compiler, it easily might not
be for others. The language imposes no requirement
that it be -1, only that it is an integer less than zero,
i.e. between INT_MIN and -1.

[snip code, which does not prove that EOF is always -1]

-Mike

 

[Mike Wahler]

If you want to know the value of EOF

But there isn't any *need* to know. And often this
(compiler-specific) 'knowledge' can lead one to write
code which has problems if it is ported to another
compiler (or another version of the same one).

This is the whole point of having abstractions such
as 'EOF'. They weren't created just for fun.

on your compiler look in stdio.h (or
whatever io lib you are using). eg

#define EOF (-1)

or #define EOF (-42)

etc.

But there's no need to look this up (and as I noted above,
doing so can lead the ignorant to write unnecessarily
nonportable code).

Just write EOF and you have a guarantee (from the language
standard), that every compliant compiler will create code
that works correctly.

BTW Please don't top-post in comp.lang.c

-Mike