1 #include <stdio.h> 2 #include <stdint.h> 3 #include <stdlib.h> 4 #include <unistd.h> 5 #include <sys/types.h> 6 #include <sys/stat.h> 7 #include <fcntl.h> 8 #include <errno.h> 9 #include <string.h> 10 11 int main(int argc, char **argv) 12 { 13 const char *path; 14 char buf[4]; 15 int fd, rc; 16 17 if (argc < 2) { 18 fprintf(stderr, "usage: %s <path>\n", argv[0]); 19 return EXIT_FAILURE; 20 } 21 22 path = argv[1]; 23 24 /* create a test variable */ 25 fd = open(path, O_RDWR | O_CREAT, 0600); 26 if (fd < 0) { 27 perror("open(O_WRONLY)"); 28 return EXIT_FAILURE; 29 } 30 31 rc = read(fd, buf, sizeof(buf)); 32 if (rc != 0) { 33 fprintf(stderr, "Reading a new var should return EOF\n"); 34 return EXIT_FAILURE; 35 } 36 37 return EXIT_SUCCESS; 38 } 39