C Programming Code Examples
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program to implement who command
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/* 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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