FILE *fp; char str[50]; char* filename = "1.txt"; fopen_s(&fp, filename, "r"); if (fp == NULL) { printf("Could not open file %s", filename); return 1; } while (fgets(str, 50, fp) != NULL) { cout << atoi(str) << endl; } fclose(fp);
FILE *fp; if ((fp=fopen("test", "rb+")) == NULL) { printf ("Cannot open file.\n"); exit(1); }