Open For Shared Use

The Open For Shared Use menu item allows multiple users to open the same Pathloss Network file (*.GR6) from a shared drive.

In this mode, Pathloss tracks changes made to the network file and notifies other users when those changes occur. The file cannot be saved if the revision date of the file on disk does not match the revision date of the file currently in memory. This prevents one user from accidentally overwriting changes made by another user.

SHR File

The sharing mechanism uses a file with the same name as the network file, but with the extension `.SHR`. This file is referred to as the SHR file.

The SHR file contains:

• The current revision date and change number.
• A list of users who currently have the network file open.
• A series of change records used to update each user’s copy of the file.

The SHR file is created when the first user opens the network file for shared use. At that point, the file contains the user’s name and the current revision date. The change number is set to zero.

Pathloss then monitors the SHR file to determine whether the revision date has changed.

The SHR file is deleted when the last user closes the network file.

Opening a Shared Network File

After the first user has opened the network file, any additional users opening the same file are shown a list of users who already have it open.

Each new user is added to the user list and receives the current revision date at the time the file is loaded.

Saving Changes

When a user makes changes and saves the network file, Pathloss first compares the file in memory with the file on disk and creates a record of the changes.

A change is defined as one of the following:

• A site has been added, moved, or deleted.
• A link has been added or deleted.
• The Pathloss data file name associated with a link has been changed.

When the file is saved, the SHR file is updated with the new revision date, and the change record is appended to the SHR file.

Change Notifications

In a shared environment, Pathloss monitors the SHR file. If a change is detected, the user is notified and shown a list of changes. Each change can be viewed before deciding how to update the local display.

The user has the following options:

Make Changes

The changes are applied directly from the SHR file. The display is not reformatted. All changes recorded in the SHR file are applied.

Reload File

The complete network file is reloaded from disk, and the display is reformatted.

Cancel

If Cancel is clicked, the network display is not updated. The user may update the display later by reopening the file using the **Files - Open for shared use** menu item.

Only one change notification is issued if the user chooses not to reload or update the file. Once the file has been updated, change notifications will resume.

Recommended best practices for using Open For Shared Use

• Store shared *.GR6 and related *.PL6 files on a reliable SMB file server.
• Ensure all users open the shared network file using Open for Shared Use.
• Avoid copying the active network file locally while others are editing it.
• Ensure users have read/write/create/delete permissions in the project folder, since the SHR file must be created and removed.
• Use regular backups or file versioning on the project folder.
• Avoid using consumer file-sync tools such as OneDrive, Dropbox, or similar services for active shared-use project folders unless they have been specifically tested, as file synchronization delays can interfere with multi-user coordination.
• Keep terrain, map cache, and large supporting datasets in clearly separated folders to simplify backup and maintenance. (Optional)