1 /* 2 * Copyright (c) 1983 Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms are permitted 6 * provided that the above copyright notice and this paragraph are 7 * duplicated in all such forms and that any documentation, 8 * advertising materials, and other materials related to such 9 * distribution and use acknowledge that the software was developed 10 * by the University of California, Berkeley. The name of the 11 * University may not be used to endorse or promote products derived 12 * from this software without specific prior written permission. 13 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 14 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 15 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 16 */ 17 18 #if defined(LIBC_SCCS) && !defined(lint) 19 static char sccsid[] = "@(#)seekdir.c 5.4 (Berkeley) 01/11/89"; 20 #endif /* LIBC_SCCS and not lint */ 21 22 #include <sys/param.h> 23 #include <dirent.h> 24 25 /* 26 * seek to an entry in a directory. 27 * Only values returned by "telldir" should be passed to seekdir. 28 */ 29 void 30 seekdir(dirp, loc) 31 register DIR *dirp; 32 long loc; 33 { 34 long curloc, base, offset; 35 struct dirent *dp; 36 extern long lseek(); 37 38 curloc = telldir(dirp); 39 if (loc == curloc) 40 return; 41 base = loc & ~(DIRBLKSIZ - 1); 42 offset = loc & (DIRBLKSIZ - 1); 43 (void) lseek(dirp->dd_fd, base, 0); 44 dirp->dd_loc = 0; 45 while (dirp->dd_loc < offset) { 46 dp = readdir(dirp); 47 if (dp == NULL) 48 return; 49 } 50 } 51