1 /* 2 * Copyright (c) 1988 The 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[] = "@(#)ttyname.c 5.4 (Berkeley) 09/11/89"; 20 #endif /* LIBC_SCCS and not lint */ 21 22 #include <sys/types.h> 23 #include <sys/dir.h> 24 #include <sys/stat.h> 25 #include <sgtty.h> 26 #include <paths.h> 27 28 char * 29 ttyname(fd) 30 int fd; 31 { 32 register struct direct *dirp; 33 register DIR *dp; 34 struct stat sb1, sb2; 35 struct sgttyb ttyb; 36 static char buf[sizeof(_PATH_DEV) + MAXNAMLEN] = _PATH_DEV; 37 char *rval, *strcpy(); 38 39 if (ioctl(fd, TIOCGETP, &ttyb) < 0) 40 return(NULL); 41 if (fstat(fd, &sb1) < 0 || (sb1.st_mode&S_IFMT) != S_IFCHR) 42 return(NULL); 43 if ((dp = opendir(_PATH_DEV)) == NULL) 44 return(NULL); 45 for (rval = NULL; dirp = readdir(dp);) { 46 if (dirp->d_ino != sb1.st_ino) 47 continue; 48 (void)strcpy(buf + sizeof(_PATH_DEV) - 1, dirp->d_name); 49 if (stat(buf, &sb2) < 0 || sb1.st_dev != sb2.st_dev || 50 sb1.st_ino != sb1.st_ino) 51 continue; 52 closedir(dp); 53 rval = buf; 54 break; 55 } 56 closedir(dp); 57 return(rval); 58 } 59