Tcl Core IO System

The Tcl IO subsystem provides various Tcl C API functions and is is used by chan and socket.

See Also

Tcl IO Drivers aka The Tcl I/O system as seen by a driver (channel type), by AKU
Describes the I/O system used in the Tcl core as it is seen from a driver implementing a channel type.
The interaction between the I/O subsystem and the notifier
A description of the connections between I/O and Notifier components relevant to the generation and handling of file events.
Channel Implementations
TclIOGT.c
Implements a generic transformation exposing the underlying API at the script level. Used by TestChannelCmd in the Tcl test suite. Together these pieces are a good example for constructing stacked channels at the C level.