Tcl and the Tk Toolkit, Second Edition

15. Managing Tcl Internals

This chapter describes a collection of introspection commands that allow you to query and manipulate the internal state of the Tcl interpreter and to create helper interpreters for specialized tasks. For example, you can use these commands to see if a variable exists, to monitor all uses of a variable or command, to rename or delete a command, to handle references to undefined commands, or to create an interpreter suited to executing scripts dealing with data from untrusted sources. This chapter also discusses Tcl’s features for time and date manipulation, measuring how long code execution takes, temporarily pausing script execution, and scheduling actions to take place after a delay.

15.1 Commands Presented in This ...