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program to implement who command



program to implement who command

#include<stdio.h>
#include<sys/utsname.h>
#include<utmp.h>
int main(void)
{
 struct utmp *n;
 char *a;
 int i;
 setutent();
 n=getutent();
 while(n!=NULL)
 {
  if(n->ut_type==7)
  {
   printf("%-9s",n->ut_user);
   printf("%-12s",n->ut_line);
   a=ctime(&n->ut_time);
   printf(" ");
   for(i=4;i<16;i++)
   printf("%c",a[i]);
   printf(" (");
   printf("%s",n->ut_host);
   printf(")
");
  }
  n=getutent();
 }
}

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