topic Re: get userlist from HPUX whose primary group is given in Operating System - Linux

get userlist from HPUX whose primary group is given

pjena — Tue, 04 Jul 2006 07:26:31 GMT

Hi,
I want to get the username list whose primary group is given on HPUX.
I used following program to get the username

main()
{
int i=0;
struct group* grp;
grp = getgrnam("adm_system");
if(grp)
{
printf("%s\n",grp->gr_name);
printf("%s\n",grp->gr_passwd);
printf("%d\n",grp->gr_gid);
while (grp->gr_mem[i] !=NULL)
{
printf("%s\n",grp->gr_mem[i])
i++;
}
}
}
But it is displaying the user list whose secondary group is "adm_system" and also tried with getgrgid(), but it doesn't give the proper result.

Please help me to get the user list whose primary group is "adm_system"

Regards,
Prasant

Re: get userlist from HPUX whose primary group is given

Victor BERRIDGE — Tue, 04 Jul 2006 07:31:29 GMT

Hi

For example GID= bin :
cat /etc/passwd|grep ":2:"

All the best
Victor

Re: get userlist from HPUX whose primary group is given

Peter Godron — Tue, 04 Jul 2006 07:38:13 GMT

Prasant,
thread http://forums1.itrc.hp.com/service/forums/bizsupport/questionanswer.do?threadId=849713 shows how to get the reverse of the info without C.

So for your case,
get the gid for "adm_system" from /etc/group then look in /etc/passwd for this gid.

Re: get userlist from HPUX whose primary group is given

Darrel Louis — Tue, 04 Jul 2006 07:44:02 GMT

Hi Prasant,

Have you tried the logins command:
# logins -g

For more info see man logins.

Darrel

Re: get userlist from HPUX whose primary group is given

Peter Godron — Tue, 04 Jul 2006 08:20:46 GMT

Prasant:
#include
#include
main()
{
int i=0;
struct group* grp;
struct passwd* pwd;
grp = getgrnam("adm_system");
if(grp)
{
printf("Group Name %s\n",grp->gr_name);
printf("GRPID %d\n",grp->gr_gid);
while (grp->gr_mem[i] !=NULL)
{
printf("Users from Group file : %s\n",grp->gr_mem[i]);
i++;
}
while (pwd=getpwent())
{
if (pwd->pw_gid == grp->gr_gid) printf("Users from Password file : %s\n",pwd->pw_name);
}
}
}

Re: get userlist from HPUX whose primary group is given

Stefan Schulz — Tue, 04 Jul 2006 08:57:39 GMT

Hi,

do you really need to programm it by yourselfe? There is a tool in HP-UX called "logins" that allready does what you want.

Do you just need the information? Then logins should be helpfool to you.

Or do you need a function in your own programs?

Regards Stefan

Re: get userlist from HPUX whose primary group is given

Victor BERRIDGE — Tue, 04 Jul 2006 10:56:06 GMT

Sorry
I missed the fact you could me using NIS...
In this case as suggested the use of logins -g | grep should do the trick under HPUX

All the best
Victor

Re: get userlist from HPUX whose primary group is given

A. Clay Stephenson — Tue, 04 Jul 2006 16:25:52 GMT

Bear in mind that you don't need to search the group file (or map) for primary group membership. In fact, the presense of a login in the group files means nothing as it applies to primary group membership. Primary group member ship is determined solely by the GID value in the user's passwd entry. The only reason to consult the group file (or map) is to obtain the GID of the group. You then scan the passwd file (or map) for matching GID entries.

The standard libc passwd and group file functions will automatically include the NIS data, if applicable.

#include
#include
int main()
{

struct group *grp;

grp = getgrnam("adm_system");
if(grp != NULL)
{
struct passwd *pwd = NULL;

printf("Group Name %s\n",grp->gr_name);
printf("GRPID %d\n",grp->gr_gid);

do
{
pwd = getpwent;
if (pwd != NULL)
{
if (pwd->pw_gid == grp->gr_gid) printf("%s\n",pwd->pw_name);
}
}
while (pwd != NULL);
}
return(0);
}