Javascript Corruption In Vagrant Shared Folders

If you are serving javascript files from your typical LAMP stack in Vagrant using shared folders, you will hit a problem where the JS files will be served truncated at arbitrary lengths. Curiously, this does not seem to affect other static text file types and it could be a combination of headers and caching that is responsible for this.
By the looks of it, the problem is not something that’s new.  This thread from the Virtualbox forums addresses the same issue and it goes back all the way to 2009. And the last post in the thread provides the right solution, which is to turn off sendfile in httpd config.
Curiously, EnableSendFile defaults to ‘off’ in the stock installation, but disabling it specifically gets rid of the problem. This should be fun to dig into and unravel, but I will leave that for another day.

Never mind.