Directory Change

The Directory Change task monitor polls a single directory (or file) for changes.  The Directory Change task can be used in three ways:
1) If a change is detected in this task, you can run another task and exit.
2) You can set this task to run as a daemon, which continuously polls the directory/file for changes, and keeps triggering another task.  This is very useful in production environments, where files are continuously moving into a folder.  For example, when a change is detected, you can continuously launch a file processing script.  Then continue polling for changes.
3) The Directory Change task can also be embedded within a Chain task. The Directory Change task is useful for conditional task processing. If you want to use this task in a chain for conditional processing, select 'None' as the 'Task To Run'.  If the criteria is satisfied, then an exit code = -100 is thrown.  Else, an exit code = 0 is thrown.

IMPORTANT: This task only detects changes while the task is running. So, if you start/restart the engine at 10:00 AM, and if your next DirChange task is at 10:30 AM, any directory changes between 10:00 AM - 10:30 AM will go undetected. This task is best used on servers, where you do not have to restart the engine often.

Directory
Enter the directory or file you need to monitor.

Task To Run
Select the desired task to run if any of the selected criteria are met.  If you want to use this task in a chain for conditional processing, select 'None'.  You can also select multiple tasks, to run in sequence or, to run simultaneously. To run tasks in sequence, use taskTitle1|taskTitle2|taskTitle3. To run tasks simultaneously, use taskTitle1&taskTitle2&taskTitle3.

Maximum wait time
Set the maximum allowed time to wait for a change to occur (T1).

Polling Interval
Enter the polling interval (in seconds). The default value of 60 seconds is recommended.  You can choose a smaller interval if you need to.

Use as Daemon
Select this option if you need to continuously poll a directory for changes and trigger another task to run.  This demon option should not be used when this task is running in a chain.
To monitor a directory continuously, do the following:
Set the maximum wait time (T1) for the task = 60 minutes.  Schedule this task to run once an hour.  i.e. when the previous schedule ends, a new schedule is started.

• Create a "DirChange" task with the directory or the file you need to monitor for changes.
• Create a Chain Task with the above "DirChange" task as the 1st step.
• Set the maximum wait time (T2) to be greater than T1 above.
• Use the Exit Code criteria as (if Exit Code != -100 Go to Step 10) i.e. stop chain if exit code != -100
• Add a second task after this step.
• Set this Chain to run at time = X.
• Set another task type like (ftp, program etc.) to run at time = X+1 minutes
• On successful completion, the other task type (ftp, program etc.) should generate/copy/move/delete a file in the desired directory.
• If a directory change is detected, the DirChange task will exit with Exit Code = -100 and the Chain will run the 2nd task.
• If the task wait time (T1) is exceeded, the DirChange task will exit with Exit Code != -100 and the Chain will terminate without running the 2nd task.

Difference between Directory Change and Directory Monitor Tasks
Directory Change task keeps polling the directory for the maximum time set.  When the maximum time expires, or a change is detected, this task either exits, or continues polling as a daemon.  This task can only monitor a single directory, or a single file.
Directory Monitor task stores (in a log file), the modified date information for all files within the directory.  This log file is read, and updated, with every run. The Directory Monitor task compares the modified date (stored in the log file) with the actual modified date of the file.  This task can also monitor sub directories.