TclX
TclX, an abbreviation for extended Tcl, was one of the first freely available Tcl extensions to the Tcl programming language, providing new operating system interface commands, extended file controls, time and date manipulation, scanning and status commands and many others. While many features of TclX have been incorporated into Tcl, TclX continued to be updated, providing Tcl interfaces to many Unix/Linux system calls and library routines, expanded list functions, and so forth.