There are 2 file types use the .TBD file extension:
1. Visual Studio Toolbox Data File
File created by Microsoft Visual Studio, a Windows software development application; cache referenced by Visual Studio's tool function to optimize the load time; contains metadata for the current visual appearance and the original visual appearance, for when you select; not meant to be manually opened.
TBD files are located in C:\Users\USERPROFILE\Local Settings\Application Data\Microsoft\VisualStudio\YOURVERSION\.
TBD files are hidden, to show them, open Windows Explorer, select, then check the "Hidden Items" box. Hidden files, including your TBD files, should now be visible.
|Microsoft Visual Studio||Commercial|
Updated: February 17, 2014
2. Apple Xcode Text-based Definition File
A TBD file is a text-based file used by Apple Xcode, a macOS IDE used to develop iOS and macOS apps. It contains information about a .DYLIB library, the location of the DYLIB library, and symbols. TBD files were introduced in Xcode 7 in September 2015 in order to reduce the size of SDKs that come with Xcode by linking to DYLIB libraries instead of storing the actual, larger DYLIB libraries.
TBD files are referenced by Xcode and are not meant to be opened. However, they can be viewed in a text editor since they are stored in plain text.
TBD files can be found in the /usr/lib of Developer/SDKs/MacOSX.sdk, which is contained in the following path:
The files may also be found in similar paths for other platforms, such as AppleTVOS.platform, iPhoneOS.platform, and WatchOS.platform.
Updated: December 6, 2018