`cputime', `tstart', `tstop'
----------------------------

cputime(ONOFF)
     :: $@0z?t$,(J 0 $@$J$i$P(J `cputime' $@$NI=<($r;_$a$k(J. $@$=$l0J30$J$i$PI=<($r(J
     $@9T$&(J.
tstart()
     :: CPU time $@7WB,3+;O(J.
tstop()
     :: CPU time $@7WB,=*N;$*$h$SI=<((J.

RETURN
     0
ONOFF
     $@%U%i%0(J ($@G$0U(J)

   * `cputime()' $@$O(J, $@0z?t$,(J 0 $@$J$i$P(J CPU time $@$NI=<($r;_$a$k(J. $@$=$l0J30(J
     $@$J$i$PI=<($r9T$&(J.
   * `tsart' $@$O0z?t$J$7(J, `()' $@$J$7$G(J, CPU time $@7WB,$r3+;O$9$k(J.
   * `tstop' $@$O0z?t$J$7(J, `()' $@$J$7$G(J, CPU time $@7WB,$r=*N;(J, $@$*$h$SI=<((J
     $@$9$k(J.
   * `cputime(ONOFF)' $@$O(J `ctrl("cputime",ONOFF)' $@$HF1$8$G$"$k(J.
   * `tstart', `tstop' $@$O(J, $@F~$l;R$K$7$F;H$o$l$k$3$H$OA[Dj$7$F$$$J$$$?(J
     $@$a(J, $@$=$N$h$&$J2DG=@-$,$"$k>l9g$K$O(J, `time()' $@$K$h$k7WB,$r9T$&I,MW(J
     $@$,$"$k(J.
   * `cputime()' $@$K$h$k(J on, off $@$O(J, $@C1$KI=<($N(J on, off $@$G$"$j(J, $@%H%C%W(J
     $@%l%Y%k$N0l$D$NJ8$KBP$9$k7WB,$O>o$K9T$o$l$F$$$k(J. $@$h$C$F(J, $@7W;;$r;O(J
     $@$a$F$+$i$G$b(J, $@7W;;=*N;A0$K%G%P%C%,$KF~$C$F(J `cputime(1)' $@$r<B9T$5(J
     $@$;$l$P7W;;;~4V$OI=<($5$l$k(J.

     [49] tstart$
     [50] fctr(x^10-y^10);
     [[1,1],[x+y,1],[x^4-y*x^3+y^2*x^2-y^3*x+y^4,1],[x-y,1],
     [x^4+y*x^3+y^2*x^2+y^3*x+y^4,1]]
     [51] tstop$
     80msec + gc : 40msec
     [52] grm(katsura(4),[u4,u3,u2,u1,u0])$
     ^Cinterrupt ?(q/t/c/d/w/?) d
     stopped in gbcheck at line 186 in file "./gb/gr"
     186                     if ( !ZERO(H) )
     (debug) print cputime(1)                 
     cputime(1) = 0
     (debug) c
     580msec + gc : 320msec
     [53] 

$@;2>H(J
     `time', `ctrl'

