...loopctlfd, loopfd, backingfile; long devnr; char loopname[4096]; if (argc != 2) { fprintf(stderr, "Usage: %s backing-file\n", argv[0]); exit(EXIT_FAILURE); } loopctlfd = open("/…...loopctlfd, loopfd, backingfile; long devnr; char loopname[4096]; if (argc != 2) { fprintf(stderr, "Usage: %s backing-file\n", argv[0]); exit(EXIT_FAILURE); } loopctlfd = open("/…