Solve exercise 8-3: fflush and fclose

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diff --git a/ch8/8-03_fflush-and-fclose.c b/ch8/8-03_fflush-and-fclose.c
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+#include <errno.h>
+#include <string.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include "syscalls.h"
+/* The C Programming Language: 2nd Edition
+ *
+ * Exercise 8-3: Design and write `_flushbuf`, `fflush`, and `fclose`.
+ *
+ * Notes: Not much guidance here, eh? :) We'll want to consult manpages.
+ *
+ * _flushbuf returns 0 on success, -1 on failure.
+ * fflush flushes a buffer, or *all* buffers
+ * fclose does housekeeping on _iob members so fds can be juggled
+ *
+ * Since work done in these exercises is predominantly in a header file, the
+ * final implementation is used for all exercises that rely on it. Attempts
+ * have been made to demonstrate *what* is being done, but it's difficult to do
+ * so without creating side effects inside the buffers themselves. Trust that
+ * if this file outputs its own source, everything is fine.
+ */
+
+int main() {
+	/* Let's copy 8-2's exercise but get a different look on the buffer. */
+	/* show the contents of buffers before and after flush */
+	FILE *fp = fopen("8-03_fflush-and-fclose.c", "r");
+	if (fp != NULL) {
+		char c;
+		while ((c = getc(fp)) != EOF) {
+			putchar(c);
+		}
+		/* fclose calls fflush */
+		fclose(fp);
+		fclose(stdout);
+	} else {
+		puts("Could not open file for reading.");
+	}
+	return 0;
+}