Re: was there a more fine number than $SECONDS for the same purpose

[Alex fxmbsw7 Ratchev]

On Sun, Nov 7, 2021, 15:02 Tapani Tarvainen <bash@tapanitarvainen.fi> wrote:

> On Sun, Nov 07, 2021 at 03:34:12PM +0200, Tapani Tarvainen (
> bash@tapanitarvainen.fi) wrote:
>
> > On Sun, Nov 07, 2021 at 08:17:56AM -0500, Greg Wooledge (
> greg@wooledge.org) wrote:
> >
> > > You can store the value of EPOCHREALTIME in a different variable at the
> > > start of your script, and then retrieve it again later on, and subtract
> > > the two.  However, subtracting the two values will require forking an
> > > external program, because bash can't do it.
> >
> > Well bash can do it, if you save the values as microseconds.
> > $EPOCHREALTIME always has six decimal points, it doesn't omit
> > trainling zeroes, so it's pretty easy. E.g.,
> >
> > START=${EPOCHREALTIME/[[:punct:]]/}
> > ...
> > NOW=$(( ${EPOCHREALTIME/[[:punct:]]/} - START ))
>
> Or keep them as seconds and just do the math in microseconds,
> here simplified by assuming period as decimal point:
>
> START=$EPOCHREALTIME
> ...
> STOP=$EPOCHREALTIME
> MUSDIFF=$(( ${STOP/./} - ${START/./} ))
> SDIFF=${MUSDIFF::-6}.${MUSDIFF: -6:6}
>
> To cover locales with different decimal points, this should work:
>
> ...
> RADIX=${EPOCHREALTIME//[[:digit:]]/}
> MUSDIFF=$(( ${STOP/$RADIX/} - ${START/$RADIX/} ))
> SDIFF=${MUSDIFF::-6}$RADIX${MUSDIFF: -6:6}
>
> Incidentally, is there any easier way to determine the decimal
> point in current locale?
>
i didnt get any problems seen by time.now - time.before in gawk , ..

>
> --
> Tapani Tarvainen
>
>