1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Author: SeongJae Park <sj@kernel.org>
4  */
5 
6 #include <fcntl.h>
7 #include <stdlib.h>
8 #include <unistd.h>
9 #include <stdio.h>
10 
11 void write_read_with_huge_count(char *file)
12 {
13 	int filedesc = open(file, O_RDWR);
14 	char buf[25];
15 	int ret;
16 
17 	printf("%s %s\n", __func__, file);
18 	if (filedesc < 0) {
19 		fprintf(stderr, "failed opening %s\n", file);
20 		exit(1);
21 	}
22 
23 	write(filedesc, "", 0xfffffffful);
24 	perror("after write: ");
25 	ret = read(filedesc, buf, 0xfffffffful);
26 	perror("after read: ");
27 	close(filedesc);
28 }
29 
30 int main(int argc, char *argv[])
31 {
32 	if (argc != 2) {
33 		fprintf(stderr, "Usage: %s <file>\n", argv[0]);
34 		exit(1);
35 	}
36 	write_read_with_huge_count(argv[1]);
37 
38 	return 0;
39 }
40