Tornado

Tornado 2.0
User’s Guide
tclerror
Toggles Tcl verbose error printing, to help debug Tcl scripts. When verbose
error mode is ON, the entire stack of error information maintained by the Tcl
interpreter appears when a Tcl error occurs that is not caught. Otherwise,
when verbose error mode is OFF, only the innermost error message is printed.
For example:
(gdb) tcl puts stdout [expr $x+2]
can’t read "x": no such variable
(gdb) tclerror
TCL verbose error reporting is ON.
(gdb) tcl puts stdout [expr $x+2]
can’t read "x": no such variable
while executing
"expr $x..."
invoked from within
"puts stdout [expr $x..."
Tcl also stores the error stack in a global variable, errorInfo. To see the error stack
when Tcl verbose error mode is OFF, examine this variable as follows:
(gdb) tcl $errorInfo
For more information about error handling in Tcl, see B.2.9 Tcl Error Handling,
p.324.
7.6.3 Tcl: Invoking GDB Facilities
You can access GDB facilities from Tcl scripts with the following Tcl extensions:
gdb arguments
Executes a GDB command (the converse of the GDB tcl command). Tcl
evaluates the arguments, performing all applicable substitutions, then
combines them (separated by spaces) into one string, which is passed to GDB’s
internal command interpreter for execution.
If the GDB command produces output, it is shown in the command panel.
If Tcl debugging is enabled (with tcldebug), the following message is printed:
execute: command
If the GDB command causes an error, the Tcl procedure gdb signals a Tcl error,
which causes unwinding if not caught (for information about unwinding, see
B.2.9 Tcl Error Handling, p.324).
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