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16#include <unistd.h>
17#include <sys/syscall.h>
18#include <sys/types.h>
19#include <sys/stat.h>
20#include <fcntl.h>
21#include <errno.h>
22#include <string.h>
23#include <stdio.h>
24
25static inline ssize_t sys_read(int fd, void *buf, size_t len)
26{
27 return syscall(SYS_read, fd, buf, len);
28}
29
30int main(void)
31{
32 char buf1[64];
33 char buf2[64];
34 int fd;
35 ssize_t rv;
36
37 fd = open("/proc/self/syscall", O_RDONLY);
38 if (fd == -1) {
39 if (errno == ENOENT)
40 return 4;
41 return 1;
42 }
43
44
45 snprintf(buf1, sizeof(buf1), "%ld 0x%lx 0x%lx 0x%lx",
46 (long)SYS_read, (long)fd, (long)buf2, (long)sizeof(buf2));
47
48 memset(buf2, 0, sizeof(buf2));
49 rv = sys_read(fd, buf2, sizeof(buf2));
50 if (rv < 0)
51 return 1;
52 if (rv < strlen(buf1))
53 return 1;
54 if (strncmp(buf1, buf2, strlen(buf1)) != 0)
55 return 1;
56
57 return 0;
58}
59