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
write_read_with_huge_count(char * file)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
main(int argc,char * argv[])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