What is a TCL file? A TCL file is a script written in the Tool Command Language (Tcl), a lightweight scripting language designed for issuing commands to programs and automating tasks. Developers use TCL files to automate processes, test applications, build user interfaces (often with the help of the Tk toolkit), or extend the functionality of tools like EDA (Electronic Design Automation) software, network routers, and simulation systems.

More Information While Tcl (pronounced "tickle") is not as widely used as other scripting languages, some developers still use it for quickly writing and modifying scripts that interact with other applications or systems because of its syntax simplicity and portability. The scripts are used in a wide range of software environments and are especially common in engineering and embedded system contexts, where it is helpful for writing configuration scripts and test cases. NOTE: John Ousterhout developed the Tcl scripting language in the late 1980s while working at the University of California, Berkeley. Now, the Tcl Core Team maintains it under the guidance of the Tcl Developer Xchange, an open-source community that oversees its ongoing development.