Much  of  the  function  of CHKWEEK  is  replaced  by  the  system  Job
Scheduler.

In  some  environments it  is  desirable  to perform  a  function on  a
specific  day of  the week  (e.g.   Monday).   For example,  assume you
want to  perform a fixed  set of  functions when you  signon on  Monday
morning.   The CHKWEEK command in  conjunction with a  data area allows
you  to easily  determine whether to  execute the  function.  Normally,
the CHKWEEK command would be coded within your initial program.

To use the CHKWEEK command you  must first create a data area of  *CHAR
LEN(6).  A  value must be placed into  the data area for  the first day
on  which the  function should be  executed.   The data area  should be
entered in job  date format (assume  MMDDYY in this example).   If  you
want to start  performing the function  on 12/24/09 enter the  value of
'122409'.

The CHKWEEK command  has a return variable.   The command will return a
'1'  value on 12/24/09,  12/31/09, 01/07/10, etc.   Because the command
includes a return  variable, it can only  be executed in a  CL program.

When a '1'  is returned, the data area  is updated.  If you  do not use
CHKWEEK  for several  weeks or any  time during  the week  that is past
the date specified, the data area  is updated for the most current  day
of the week and a '1' is returned.

While the  data area is  only a 6 position  date, the internals  of the
command will properly handle the change to a new century.

The typical sequence of commands would be:

         DCL         &RTNLGL *LGL
          .
          .
         CHKWEEK     DTAARA(xxxx) RTNLGL(&RTNLGL)
         IF          &RTNLGL DO /* Day of week to execute */
          .
          .              /* Your code to execute */
          .
         ENDDO       /* Day of week to execute */

The  logical value  will be  set on only  once if  the current  date is
equal or greater  than the  data area  date.   If the  command has  not
been executed for  several weeks, the logical  value is set on  and the
data area  date is set  greater than the  current date.   If the normal
date  of  execution is  on a  Monday, but  the  CHKWEEK command  is not
executed until Tuesday, the return variable will be set on Tuesday.

Differences with the system Job Scheduler
-----------------------------------------

The system Job  Scheduler function will execute  at a fixed time  every
week.   CHKWEEK allows you to tie  the execution of a  function to when
you signon or another event occurs.

Command parameters                                    *CMD
------------------

   DTAARA        The  qualified data area  which contains  the start or
                 next date.   The data  area must be  defined as  *CHAR
                 LEN(6) and be specified in system date format.

   RTNLGL        A  logical   (*LGL)  return   value  where   '1'  (on)
                 indicates that the function should be performed.

Prerequisites
-------------

The following TAA Tools must be on your system:

          ADDDAT       Add date

Implementation
--------------

The  tool is ready to  use, but you must  create a data area  to use of
*CHAR LEN(6) and place a beginning date in it.

Objects used by the tool
------------------------

   Object        Type       Attribute      Src member     Src file
   ------        -----      ---------      ----------     -----------

   CHKWEEK       *CMD                      TAADATE        QATTCMD
   TAADATEC      *PGM          CLP         TAADATEC       QATTCL