1 /* 2 * Copyright (c) 1988 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 */ 7 8 #if defined(LIBC_SCCS) && !defined(lint) 9 static char sccsid[] = "@(#)ttyname.c 5.6 (Berkeley) 06/01/90"; 10 #endif /* LIBC_SCCS and not lint */ 11 12 #include <sys/types.h> 13 #include <sys/dir.h> 14 #include <sys/stat.h> 15 #include <sgtty.h> 16 #include <paths.h> 17 18 char * 19 ttyname(fd) 20 int fd; 21 { 22 register struct direct *dirp; 23 register DIR *dp; 24 struct stat sb1, sb2; 25 struct sgttyb ttyb; 26 static char buf[sizeof(_PATH_DEV) + MAXNAMLEN] = _PATH_DEV; 27 char *rval, *strcpy(); 28 29 if (ioctl(fd, TIOCGETP, &ttyb) < 0) 30 return(NULL); 31 if (fstat(fd, &sb1) < 0 || (sb1.st_mode&S_IFMT) != S_IFCHR) 32 return(NULL); 33 if ((dp = opendir(_PATH_DEV)) == NULL) 34 return(NULL); 35 for (rval = NULL; dirp = readdir(dp);) { 36 if (dirp->d_ino != sb1.st_ino) 37 continue; 38 (void)strcpy(buf + sizeof(_PATH_DEV) - 1, dirp->d_name); 39 if (stat(buf, &sb2) < 0 || sb1.st_dev != sb2.st_dev || 40 sb1.st_ino != sb2.st_ino) 41 continue; 42 closedir(dp); 43 rval = buf; 44 break; 45 } 46 closedir(dp); 47 return(rval); 48 } 49