Even though Tcl is designed to work efficiently in a single-threaded environment, it is possible to create separate threads in Tcl. While it can be used for performing any action, it is usually used for operations that take a lot of time to complete.
Threads in Tcl require that Tcl is built with threading enabled and has the package
Thread installed, which is true for all ActiveTcl installations. Tcl builds from various operating system distributions may or may not be built with thread support enabled—in this case, the
Thread package may not be present.
Tcl uses that approach that each thread is a separate entity and data is not normally shared across threads. It is possible to send commands to be evaluated ...