/* * ln [ -f ] target [ new name ] */#include <sys/types.h>#include <sys/stat.h>#include "stdio.h"char	*rindex();main(argc, argv)char **argv;{	struct stat statb;	register char *np;	int fflag = 0;	char nb[100], *name=nb, *arg2;	int statres;	if (argc >1 && strcmp(argv[1], "-f")==0) {		argc--;		argv++;		fflag++;	}	if (argc<2 || argc>3) {		printf("Usage: ln target [ newname ]\n");		exit(1);	}	np = rindex(argv[1], '/');	if (np==0)		np = argv[1];	else		np++;	if (argc==2)		arg2 = np;	else		arg2 = argv[2];	statres = stat(argv[1], &statb);	if (statres<0) {		printf ("ln: %s does not exist\n", argv[1]);		exit(1);	}	if (fflag==0 && (statb.st_mode&S_IFMT) == S_IFDIR) {		printf("ln: %s is a directory\n", argv[1]);		exit(1);	}	statres = stat(arg2, &statb);	if (statres>=0 && (statb.st_mode&S_IFMT) == S_IFDIR)		sprintf(name, "%s/%s", arg2, np);	else		name = arg2;	if (link(argv[1], name)<0) {		perror("ln");		exit(1);	}	exit(0);}