Version 2 of Hacking on The Core

Hacking on The Core — it's good for the soul!

Some Debugging Macros

PYK 2015-04-25: I'm still learning the ropes of C, but I'll throw these here anyway. They came in handy recently to debug an I/O/thread issue.

#define tdebug(statement) \
    fprintf(stderr, "%p: %s\n", Tcl_GetCurrentThread(), (statement))

#define tcdebug(statePtr, statement) \
    fprintf(stderr, "%p: chan %s: %s\n", Tcl_GetCurrentThread(), (statePtr)->channelName, (statement))

AMG: Minor, minor style tweaks, though the macros look good and useful for situations where you can't use the Tcl I/O or command return mechanisms. The do ... while (0) trick is not necessary when the macro is just a single function call. Arguments to be expanded almost always should be surrounded by parentheses, and you do this, but you had (statePtr->channelName) rather than (statePtr)->channelName.