vcvarsall:tldr:2497d

The command "vcvarsall x64" is used to set up the necessary environment variables for compiling C/C++ code with the Visual C++ compiler in a 64-bit environment.

When you install Visual Studio, it provides a command prompt shortcut called "Developer Command Prompt for Visual Studio." This command prompt has all the necessary environment variables already set up to compile code with the corresponding version of Visual C++ that was installed. However, if you prefer to use a different command prompt or want to use the 64-bit version of the compiler, you may need to manually set up the environment variables.

The "vcvarsall x64" command is a shortcut to automate this process. It sets up the required environment variables for the 64-bit version of the Visual C++ compiler. This enables you to compile code targeting 64-bit platforms without having to manually configure the environment variables yourself.

Once the "vcvarsall x64" command is executed, you can use the appropriate compiler commands such as "cl" (for compiling) or "link" (for linking) to build your C/C++ projects.