1 /* Test whether /proc/{self,$PID}/path/a.out is correctly simulated. */ 2 3 #include <limits.h> 4 #include <stdio.h> 5 #include <strings.h> 6 #include <unistd.h> 7 #include <sys/fcntl.h> 8 9 static void test_readlink(const char *cwd, const char *label, 10 const char *path) 11 { 12 char buf[PATH_MAX]; 13 int n; 14 15 if ((n = readlink(path, buf, sizeof(buf) - 1)) >= 0) { 16 const char *p; 17 size_t len = strlen(cwd); 18 19 buf[n] = '\0'; 20 21 p = buf; 22 if (!strncmp(buf, cwd, len)) 23 p += len; 24 printf("Result of readlink(\"%s\"): %s\n", label, p); 25 } 26 else 27 perror("readlink"); 28 } 29 30 static void test_readlinkat(const char *cwd, const char *label, 31 const char *path) 32 { 33 char buf[PATH_MAX]; 34 int n; 35 36 if ((n = readlinkat(AT_FDCWD, path, buf, sizeof(buf) - 1)) >= 0) { 37 const char *p; 38 size_t len = strlen(cwd); 39 40 buf[n] = '\0'; 41 42 p = buf; 43 if (!strncmp(buf, cwd, len)) 44 p += len; 45 printf("Result of readlinkat(\"%s\"): %s\n", label, p); 46 } 47 else 48 perror("readlinkat"); 49 } 50 51 int main(void) 52 { 53 char cwd[PATH_MAX]; 54 char path[PATH_MAX]; 55 56 cwd[0] = '\0'; 57 if (!getcwd(cwd, sizeof(cwd) - 1)) /* '-1' to make room for '/' */ 58 perror("getcwd"); 59 strcat(cwd, "/"); 60 61 snprintf(path, sizeof(path), "/proc/%ld/path/a.out", (long)getpid()); 62 63 test_readlink(cwd, "/proc/self/path/a.out", "/proc/self/path/a.out"); 64 test_readlink(cwd, "/proc/<pid>/path/a.out", path); 65 66 test_readlinkat(cwd, "/proc/self/path/a.out", "/proc/self/path/a.out"); 67 test_readlinkat(cwd, "/proc/<pid>/path/a.out", path); 68 69 return 0; 70 } 71 72
