The environment variable used to enable the polling file watcher has been renamed

[victorhurdugaci]

Before

• Razor (through FileSystem) was using ASPNETCORE_POLL_FOR_FILE_CHANGES
• Dotnet watch was using USE_POLLING_FILE_WATCHER

After

• everyone uses DOTNET_USE_POLLING_FILE_WATCHER

PRs

• Rename the environment variable used for polling watcher DotNetTools#115
• Rename the environment variable used for polling watcher FileSystem#197

Background

The DOTNET_USE_POLLING_FILE_WATCHER environment variable, if set to 1 or true, will change the file watchers to switch to a polling mode rather that relying on the OS to notify about a file change. There's a small performance hit and memory increase when using the polling watcher.

The polling file watchers are mostly used in Docker when running code from a shared volume.