The "ninja" command is a build system commonly used in software development. It is used to efficiently build large projects with multiple dependencies. Ninja is known for its fast and parallel execution. When the "ninja" command is executed, it reads a "build.ninja" file (usually present in the project directory) that defines the build rules and dependencies for the project.
The "build.ninja" file is typically generated by a higher-level build system like CMake, which converts human-readable build configuration files into a machine-readable format compatible with Ninja. The "build.ninja" file specifies how source files should be compiled, linked, and organized into the final executable or library.
When you run the "ninja" command, it analyzes the build graph and determines which tasks need to be executed based on the dependency rules defined in the "build.ninja" file. It then executes these tasks in parallel, taking full advantage of available system resources to build the project as efficiently as possible. By using Ninja, developers can significantly speed up the build process for their projects.