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From: Peng Yu <pengyu.ut@gmail.com>
Date: Tue, 11 May 2021 08:27:46 -0500
Message-ID: <CABrM6wk_Y-Xff+=ZwHZjm-LMkFuG2OpQG9rzkLfp_c3qnX9D3Q@mail.gmail.com>
Subject: EOF is a misnomer?
To: libc-help@sourceware.org
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man getchar says

"       fgetc(), getc(), and getchar() return the character read as an unsigned
       char cast to an int or EOF on end of file or error."

EOF literally stands for end of file. But the above functions can
return EOF when there is an error.

In feof(), "eof" just means end of file as shown in man feof.

       The function feof() tests the  end-of-file  indicator  for  the  stream
       pointed  to by stream, returning nonzero if it is set.  The end-of-file
       indicator can be cleared only by the function clearer().

So the macro name EOF is a misnomer. It could have been named as
something like EOF_OR_ERR? The fact that its name is EOF is due to
some historical reasons? Thanks.

-- 
Regards,
Peng