( macskas | 2009. 05. 03., v – 17:38 )

BEGIN { FS = ";" }
/^.+;login/ {
    felhasznalok[$1]++;
    split($3,a,"-");split($4,b,":");
    lin[$1]=lin[$1]+mktime(a[1]" "a[2]" "a[3]" "b[1]" "b[2]" "b[3]"00");
}
/^.+;logoff/ {
    split($3,a,"-");split($4,b,":");
    lout[$1]=lout[$1]+mktime(a[1]" "a[2]" "a[3]" "b[1]" "b[2]" "b[3]"00");
}
END {
    for (i in felhasznalok) {
        t=lout[i]-lin[i];
        m = int(t/3600);
        s = int(t % 3600/60);
        print i": "felhasznalok[i]" alkalom,"m" ora "s" perc";
    }
}

osszedobtam egy kis scriptet ezen elindulhatsz