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-rw-r--r--doc/Panic.327
1 files changed, 10 insertions, 17 deletions
diff --git a/doc/Panic.3 b/doc/Panic.3
index 454d313..28d56fa 100644
--- a/doc/Panic.3
+++ b/doc/Panic.3
@@ -33,9 +33,7 @@ Must have been initialized using \fBva_start\fR,
and cleared using \fBva_end\fR.
.AP Tcl_PanicProc *panicProc in
Procedure to report fatal error message and abort.
-
.BE
-
.SH DESCRIPTION
.PP
When the Tcl library detects that its internal data structures are in an
@@ -51,33 +49,31 @@ same formatting rules are also used by the built-in Tcl command
In a freshly loaded Tcl library, \fBTcl_Panic\fR prints the formatted
error message to the standard error file of the process, and then
calls \fBabort\fR to terminate the process. \fBTcl_Panic\fR does not
-return.
+return. On Windows, when a debugger is running, the formatted error
+message is sent to the debugger in stead. If the windows executable
+does not have a stderr channel (e.g. \fBwish.exe\fR), then a
+system dialog box is used to display the panic message.
.PP
\fBTcl_SetPanicProc\fR may be used to modify the behavior of
\fBTcl_Panic\fR. The \fIpanicProc\fR argument should match the
type \fBTcl_PanicProc\fR:
.PP
.CS
-typedef void Tcl_PanicProc(
+typedef void \fBTcl_PanicProc\fR(
const char *\fBformat\fR,
\fBarg\fR, \fBarg\fR,...);
.CE
.PP
After \fBTcl_SetPanicProc\fR returns, any future calls to
\fBTcl_Panic\fR will call \fIpanicProc\fR, passing along the
-\fIformat\fR and \fIarg\fR arguments. To maintain consistency with the
-callers of \fBTcl_Panic\fR, \fIpanicProc\fR must not return; it must
-call \fBabort\fR. \fIpanicProc\fR should avoid making calls into the
-Tcl library, or into other libraries that may call the Tcl library,
-since the original call to \fBTcl_Panic\fR indicates the Tcl library is
-not in a state of reliable operation.
+\fIformat\fR and \fIarg\fR arguments. \fIpanicProc\fR should avoid
+making calls into the Tcl library, or into other libraries that may
+call the Tcl library, since the original call to \fBTcl_Panic\fR
+indicates the Tcl library is not in a state of reliable operation.
.PP
The typical use of \fBTcl_SetPanicProc\fR arranges for the error message
to be displayed or reported in a manner more suitable for the
-application or the platform. As an example, the Windows implementation
-of \fBwish\fR calls \fBTcl_SetPanicProc\fR to force all panic messages
-to be displayed in a system dialog box, rather than to be printed to the
-standard error file (usually not visible under Windows).
+application or the platform.
.PP
Although the primary callers of \fBTcl_Panic\fR are the procedures of
the Tcl library, \fBTcl_Panic\fR is a public function and may be called
@@ -87,10 +83,7 @@ will be displayed.
.PP
\fBTcl_PanicVA\fR is the same as \fBTcl_Panic\fR except that instead of
taking a variable number of arguments it takes an argument list.
-
.SH "SEE ALSO"
abort(3), printf(3), exec(n), format(n)
-
.SH KEYWORDS
abort, fatal, error
-