--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test_fprintf.c	Wed Dec 03 03:04:39 2025 -0500
@@ -0,0 +1,66 @@
+#include "printf.h"
+
+#include <locale.h>
+#include <stdlib.h> /* malloc */
+#include <limits.h>
+#include <stdint.h>
+#include <limits.h>
+#include <float.h>
+
+int test_fprintf(void)
+{
+	int n, n2;
+	FILE *f1, *f2;
+
+	f1 = tmpfile();
+	f2 = tmpfile();
+
+	n = my_fprintf(f1,
+#include "test.h"
+		);
+	if (n < 0) {
+		fprintf(stderr, "my_fprintf: %s\n", my_strerror(n));
+		return -1;
+	}
+	n2 = fprintf(f2,
+#include "test.h"
+		);
+	if (n2 < 0) {
+		perror("fprintf");
+		return -1;
+	}
+
+	fseek(f1, 0, SEEK_SET);
+	fseek(f2, 0, SEEK_SET);
+
+	if (n != n2) {
+		fclose(f1);
+		fclose(f2);
+		return -1;
+	}
+
+	for (;;) {
+		int c1, c2;
+
+		c1 = fgetc(f1);
+		c2 = fgetc(f2);
+
+		if (c1 != c2) {
+			fprintf(stderr, "Got different results!!\n");
+			fprintf(stderr, " fprintf @ %ld: %c", ftell(f1), c1);
+			fprintf(stderr, " my_fprintf @ %ld: %c", ftell(f2), c2);
+
+			fclose(f1);
+			fclose(f2);
+			return -1;
+		}
+
+		if (c1 == EOF)
+			break;
+	}
+
+	fclose(f1);
+	fclose(f2);
+
+	return 0;
+}
\ No newline at end of file