Batch script for time measurement not working properly

Question

I'm using a batch script for the time measurement of commands. I have found this script here on StackOverflow. Unfortunately it sometimes is not working properly and unfortunately I don't know much about batch programming. I get the impression that it sometimes works and sometimes not. Perhaps I err on this but it does seem that its not working properly after midnight.

The script:

@echo off
setlocal

rem The format of %TIME% is HH:MM:SS,CS for example 23:59:59,99
set STARTTIME=%TIME%

rem here begins the command you want to measure
dir /s > nul
rem here ends the command you want to measure

set ENDTIME=%TIME%

echo STARTTIME %STARTTIME%

rem convert STARTTIME and ENDTIME to centiseconds

set /A STARTTIME=(1%STARTTIME:~0,2%-100)*360000 + (1%STARTTIME:~3,2%-100)*6000 + (1%STARTTIME:~6,2%-100)*100 + (1%STARTTIME:~9,2%-100)

echo STARTTIME %STARTTIME%

echo ENDTIME %ENDTIME%

set /A ENDTIME=(1%ENDTIME:~0,2%-100)*360000 + (1%ENDTIME:~3,2%-100)*6000 + (1%ENDTIME:~6,2%-100)*100 + (1%ENDTIME:~9,2%-100)

echo ENDTIME %ENDTIME%

rem calculating the duration is easy
set /A DURATION=%ENDTIME%-%STARTTIME%

rem we might have measured the time inbetween days
if %ENDTIME% LSS %STARTTIME% set set /A DURATION=%STARTTIME%-%ENDTIME%

rem outputing

echo DURATION: %DURATION% in centiseconds

endlocal
goto :EOF

I was using it half an hour ago and I got this result:

STARTTIME  1:29:25.17 
STARTTIME  1:29:25.17 
ENDTIME  1:29:27.82 
ENDTIME  1:29:27.82 
DURATION: 1 in centiseconds

So something with the lines

set /A STARTTIME=(1%STARTTIME:~0,2%-100)*360000 + (1%STARTTIME:~3,2%-100)*6000 + (1%STARTTIME:~6,2%-100)*100 + (1%STARTTIME:~9,2%-100)

and

the line

set /A ENDTIME=(1%ENDTIME:~0,2%-100)*360000 + (1%ENDTIME:~3,2%-100)*6000 + (1%ENDTIME:~6,2%-100)*100 + (1%ENDTIME:~9,2%-100)

seems to be wrong.

What is it?

Regards, David

Answer 1

The problem is with "%STARTTIME:~0,2%-100" being " 1", there is an extra space. The program then tries to find the value of (1 1) instead of (101).

The extra 1 in front should only be for systems that output the time as "01:29:25.17" (to give 101 instead of 01 which the system will interpret as octal number), but for systems that output the time as " 1:29:25.17"(Note the space in front of the 1) there is a problem (which will give 1 1).

An easy way is just to remove the 1 in STARTTIME=(1%STARTTIME:~0,2%-100)*360000 and ENDTIME=(1%ENDTIME:~0,2%-100)*360000, though that might cause a problem with other systems.

A more watertight solution would be to add two lines after the rem line:

rem convert STARTTIME and ENDTIME to centiseconds

set STARTTIME=%STARTTIME: =0%

set ENDTIME=%ENDTIME: =0%

(EDIT: Andriy M's much shorter method above)

---

There are also two set in if %ENDTIME% LSS %STARTTIME% set set /A DURATION=%STARTTIME%-%ENDTIME% which might cause a problem when trying to measure the time between days.