wedit.c

/* This program removes wtmp entries by name or tty number */

#include 
#include 
#include 
#include 

void usage(name)
char *name;
{
    printf("Usage: %s [ user | tty ]\n", name);
    exit(1);
}

void main (argc, argv)
int argc;
char *argv[];
{
    struct utmp utmp;
    int size, fd, lastone = 0;
    int match, tty = 0, x = 0;

    if (argc>3 || argc<2)
       usage(argv[0]);

    if (strlen(argv[1])<2) {
       printf("Error: Length of user\n");
       exit(1);
    }

    if (argc==3)
       if (argv[2][0] == 'l') lastone = 1;

    if (!strncmp(argv[1],"tty",3))
       tty++;

    if ((fd = open("/usr/adm/wtmp",O_RDWR))==-1) {
        printf("Error: Open on /usr/adm/wtmp\n");
        exit(1);
    }

    printf("[Searching for %s]:  ", argv[1]);

    if (fd >= 0)
    {
       size = read(fd, &utmp, sizeof(struct utmp));
       while ( size == sizeof(struct utmp) )
       {
          if ( tty ? ( !strcmp(utmp.ut_line, argv[1]) ) :
            ( !strncmp(utmp.ut_name, argv[1], strlen(argv[1])) ) &&
              lastone != 1)
          {
             if (x==10)
                printf("\b%d", x);
             else
             if (x>9 && x!=10)
                printf("\b\b%d", x);
             else
                printf("\b%d", x);
             lseek( fd, -sizeof(struct utmp), L_INCR );
             bzero( &utmp, sizeof(struct utmp) );
             write( fd, &utmp, sizeof(struct utmp) );
             x++;
          }
          size = read( fd, &utmp, sizeof(struct utmp) );
       }
    }
    if (!x)
       printf("No entries found.");
    else
       printf(" entries removed.");
    printf("\n");
    close(fd);
}