Confusion with == EOF vs feof

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I opened a file, the stream is found at the address of pointer ptr. I am attempting to see whether or not a file is blank. Using the following

if (fgetc(ptr) != EOF)

works as expected. When the file is blank, the statement is not executed. When the file is not blank, the statement is not executed.

However, using

if (!feof(ptr))

always executes the statement.

Why does this happen? Is there a way to use the feof function?

feof fgetc pointers c file
5 Answers

Late answer, however to add a helpful quote from Programming in C (4th Edition) by Stephen Kochan, p. 367:

Remember, feof() tells you that an attempt has been made to read past the end of a file, which is not the same as telling you that you just read the last data item from a file. You have to read one past the last data item for feof() to return nonzero.

Italics mine.

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