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- Committer: Bazaar Package Importer
- Author(s): Joey Hess
- Date: 2001-10-05 20:09:25 UTC
- Revision ID: james.westby@ubuntu.com-20011005200925-1crvu3veaaofavdb
Tags: upstream-1.6.5
Import upstream version 1.6.5
- files added:
- escapes
- examples
- utils
added
removed
utmp.c
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/* utmp.c Shareware Copyright by Sam Lantinga 10/6/93 */
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#include <sys/types.h>
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#include <sys/stat.h>
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#include <fcntl.h>
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#include <utmp.h>
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#include <stdio.h>
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#ifdef DEBUG_UTMP
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#undef UTMP_FILE
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#define UTMP_FILE "/tmp/utmp"
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#else
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#ifndef UTMP_FILE
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#define UTMP_FILE "/etc/utmp"
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#endif /* UTMP_FILE */
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#endif /* DEBUG_UTMP */
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/* Remove us from the utmp file, saving our entry to replace later */
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static struct utmp saved_utmp;
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static int utmp_saved=0;
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static char saved_tty[128];
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int remove_me()
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{
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struct utmp ut;
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char *tty;
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time_t now;
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if ( ! isatty(0) )
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return(-1);
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tty=(char *)ttyname(0);
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if ( tty == NULL || strlen(tty)+1 > sizeof(saved_tty) )
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return(-1);
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/* Retrieve our utmp record */
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(void) time(&now);
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if ( get_utmp(tty, &ut) == 0 ) {
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/* Save the utmp entry and tty pathname */
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utmp_saved=1;
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d_copy((char *)&ut, (char *)&saved_utmp, sizeof(ut));
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strcpy(saved_tty, tty);
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/* Clean out the entry and return */
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ut.ut_name[0]='\0';
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ut.ut_time=now;
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#ifdef USER_PROCESS
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ut.ut_type = DEAD_PROCESS;
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#endif
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#ifdef HAVE_UTHOST
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ut.ut_host[0]='\0';
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#endif
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return(set_utmp(tty, &ut));
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}
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/* Nothing to clean out, good. */
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return(0);
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}
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int replace_me()
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{
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if ( utmp_saved )
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return(set_utmp(saved_tty, &saved_utmp));
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return(0);
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}
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int get_utmp(tty, save)
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char *tty;
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struct utmp *save;
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{
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int fd;
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char *ttyptr;
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struct utmp ut;
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/* See if we can open the utmp file */
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if ( (fd=open(UTMP_FILE, O_RDWR)) < 0 )
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return(-1);
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/* Get the ttyxy form of the tty pathname if possible. */
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if ( *tty == '/' ) {
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for ( ttyptr=(tty+1); *ttyptr; ++ttyptr ) {
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if ( *ttyptr == '/' )
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break;
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}
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if ( *ttyptr == '/' )
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++ttyptr;
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} else
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ttyptr=tty;
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while (read(fd,(char *) &ut, sizeof(ut)) == sizeof(ut)) {
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if (strncmp(ttyptr, ut.ut_line, sizeof(ut.ut_line)) == 0) {
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/* Break out; we've found our entry! */
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if ( save )
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d_copy((char *)&ut, save, sizeof(ut));
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close(fd);
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return(0);
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}
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}
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/* We never found an entry for our tty */
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close(fd);
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return(-1);
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}
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int set_utmp(tty, save)
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char *tty;
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struct utmp *save;
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{
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int fd, found=0;
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char *ttyptr;
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struct utmp ut;
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/* See if we can open the utmp file */
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if ( (fd=open(UTMP_FILE, O_RDWR)) < 0 )
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return(-1);
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/* Get the ttyxy form of the tty pathname if possible. */
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if ( *tty == '/' ) {
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for ( ttyptr=(tty+1); *ttyptr; ++ttyptr ) {
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if ( *ttyptr == '/' )
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break;
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}
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if ( *ttyptr == '/' )
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++ttyptr;
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} else
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ttyptr=tty;
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while (read(fd,(char *) &ut, sizeof(ut)) == sizeof(ut)) {
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if (strncmp(ttyptr, ut.ut_line, sizeof(ut.ut_line)) == 0) {
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found=1;
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lseek(fd, -(long)sizeof(struct utmp), 1);
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break;
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}
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}
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/* Add a new entry to the utmp file if we can't find our entry */
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if ( ! found )
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{ /* Reopen to avoid a race with other end-of-utmp entries. */
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(void) close(fd);
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if ( (fd=open(UTMP_FILE, (O_RDWR|O_APPEND))) < 0 )
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return -1;
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}
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if (write(fd, (char *)save, sizeof(*save)) != sizeof(*save)) {
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(void) close(fd);
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return -1;
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}
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return(close(fd));
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}
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/* Set up a utmp entry and tty for a user */
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int addutmp(user, uid, tty)
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char *user; /* The user to add to the utmp file */
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int uid; /* The uid corresponding to user */
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char *tty; /* /dev/ttyxx */
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{
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struct stat sb;
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struct utmp ut;
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char *ttyptr;
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/* Retrieve any existing utmp entry */
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d_zero((char *)&ut, sizeof(ut));
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(void) get_utmp(tty, &ut);
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/* Get the ttyxy form of the tty pathname if possible. */
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if ( *tty == '/' ) {
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for ( ttyptr=(tty+1); *ttyptr; ++ttyptr ) {
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if ( *ttyptr == '/' )
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break;
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}
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if ( *ttyptr == '/' )
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++ttyptr;
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} else
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ttyptr=tty;
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/* Customize the utmp entry */
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strncpy(ut.ut_name, user, sizeof(ut.ut_name)-1);
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ut.ut_name[sizeof(ut.ut_name)-1]='\0';
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strncpy(ut.ut_line, ttyptr, sizeof(ut.ut_line)-1);
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ut.ut_line[sizeof(ut.ut_line)-1]='\0';
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#ifdef USER_PROCESS
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ut.ut_type=USER_PROCESS;
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ut.ut_pid=getpid();
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#endif
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#if defined(HAVE_UTHOST)
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/* remove_me() should be called before this function */
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if ( utmp_saved ) {
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strncpy(ut.ut_host, saved_utmp.ut_host, sizeof(ut.ut_host)-1);
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ut.ut_host[sizeof(ut.ut_host)-1]='\0';
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}
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#endif
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(void) time(&ut.ut_time);
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#if !defined(SOLARIS) && !defined(IRIX)
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/* Solaris and Irix machines do this automatically */
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/* Change the ownership and mode of the tty */
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if ( stat(tty, &sb) == 0 ) {
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(void) chmod(tty, 0620); /* crw--w---- */
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(void) chown(tty, uid, sb.st_gid);
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}
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#endif
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return(set_utmp(tty, &ut));
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}
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/* End a utmp entry and tty for a user and a tty */
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int delutmp(user, tty)
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char *user;
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char *tty; /* /dev/ttyxx */
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{
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struct stat sb;
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struct utmp ut;
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int retval=0;
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/* Retrieve any existing utmp entry */
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d_zero((char *)&ut, sizeof(ut));
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if ( get_utmp(tty, &ut) == 0 ) {
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/* Clear the utmp entry */
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ut.ut_name[0]='\0';
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#ifdef USER_PROCESS
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ut.ut_type=DEAD_PROCESS;
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#endif
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#if defined(HAVE_UTHOST)
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ut.ut_host[0]='\0';
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#endif
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(void) time(&ut.ut_time);
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retval=set_utmp(tty, &ut);
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}
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#if !defined(SOLARIS) && !defined(IRIX)
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/* Solaris and Irix machines do this automatically */
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/* Reset the owner and mode of the tty */
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if ( stat(tty, &sb) == 0 ) {
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(void) chmod(tty, 0666); /* crw-rw-rw- */
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(void) chown(tty, 0, sb.st_gid);
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}
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#endif
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return(retval);
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}
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