for (i = 0, j = 0; i < ngroups; i++)
if ((gr = getgrgid(groups_bygid[i])) != NULL)
groups_byname[j++] = xstrdup(gr->gr_name);
for (i = 0, j = 0; i < ngroups; i++)
if ((gr = getgrgid(groups_bygid[i])) != NULL)
groups_byname[j++] = xstrdup(gr->gr_name);