Schedule Task : 6 months from now

Question

Hi guys,

I'm tryin' to find a way (from a batch file) that I can use to create a scheduled task that will execute 6 months from now. I've looked all over the net, and I'll I've come across is AT and SCHTASKS that will schedule the task monthly ..

I'm looking for a solution that will execute this task every 6 months.

I know this will require some time/date manipulation .. finding the month (number of month) and then adding 6 to it; once it passes '12' it goes back to 1 etc .. Then lining those numbers up with the months name, and using SCHTASKS or AT to schedule the task.

I know how to use SCHTASKS to schedule a task from a batch file; I just need the code to find the month, add 6 to it, grab the months name in 6 months time, and put that into a variable so I can parse it into the SCHTASKS.

I hope this all makes sense. My english is not so great.

TIA,

Greg

Answer 1

Why not use the Windows Scheduler?

Most of the information you need is included in this article: http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/schtasks.mspx?mfr=true

You can use the monthly setting, with a value of 6 surely?

Answer 2

Here's a crazy idea: in case you want this script on a server (which isn't rebooted), you could write a batch file which waits for six months and then executes the given program. To wait for a specific number of seconds you could abuse the 'ping' command, like this:

ping -n %SECS% localhost > NUL

This command will effectively pause for %SECS% seconds and then return. To wait for six months, simply wait for something like (365 / 2) * 24 * 60 * 60 seconds.

Here's a little batch file which implements this idea:

@echo off
set CMD=echo Half a year elapsed
set /a SECS_IN_HALF_A_YEAR=365 / 2 * 24 * 60 * 60
loop_start:
ping -n %SECS_IN_HALF_A_YEAR% localhost > NUL
%CMD%
goto loop_start

I'm not saying it's pretty, but I thought it's a funky idea. Maybe some food for thought. :-)

Answer 3

you can download coreutils for windows . Then use date command like this

C:\test>gnu_date "+%Y%m%d" -d "6 months"
20110404

(it is renamed to gnu_date.exe )

I have not played with schtasks, but depending on what format of date it uses, you can change the parameters to suit schtasks

C:\test>gnu_date "+%Y-%m-%d" -d "6 months"
2011-04-04

If you need time as well

C:\test>gnu_date "+%Y-%m-%d-%H:%M:%S" -d "6 months"
2011-04-04-18:12:35

Use a for loop to save the date to a variable as desired. then pass it to schtasks for scheduling

Answer 4

Thanks to everyone who replied, and offered suggestions. I slept on it, woke up with the flu, and had a brainwave. Funny how things work out. I know this is overkill, and someone will come up with a better suggestion, but here goes anyway ..

REM Grab month number and put into variable
  FOR /F "TOKENS=1,2 eol=/ DELIMS=/ " %%A IN ('DATE/T') DO SET mm=%%B
REM Six months from now
  set /a addmm=%mm% + 6
  if %addmm% gtr 6 (set /a sixmonths=%addmm% - 12)
REM Determine month name
  if %sixmonths%==1 (set monthname=JAN)
  if %sixmonths%==2 (set monthname=FEB)
  if %sixmonths%==3 (set monthname=MAR)
  if %sixmonths%==4 (set monthname=APR)
  if %sixmonths%==5 (set monthname=MAY)
  if %sixmonths%==6 (set monthname=JUN)
  if %sixmonths%==7 (set monthname=JUL)
  if %sixmonths%==8 (set monthname=AUG)
  if %sixmonths%==9 (set monthname=SEP)
  if %sixmonths%==10 (set monthname=OCT)
  if %sixmonths%==11 (set monthname=NOV)
  if %sixmonths%==12 (set monthname=DEC)
REM Schedule Task  
  schtasks /create /TN TuneUpReminder /RU system /TR TuneUpReminder.bat /SC MONTHLY /M %monthname%

Answer 5

Since Greg's answer made me cry inside, here is some array like syntax:

for /F "tokens=%sixmonths%" %%A IN ("JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC") DO set monthname=%%A

And since there’s always more than one way to skin a bat[ch]?

set /a sixmonths=%sixmonths% * 4
set months=666 JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
setlocal ENABLEDELAYEDEXPANSION
set monthname=!months:~%sixmonths%,3!
REM Optional: setlocal DISABLEDELAYEDEXPANSION