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diff --git a/doc/bgerror.n b/doc/bgerror.n deleted file mode 100644 index 3f946c3..0000000 --- a/doc/bgerror.n +++ /dev/null @@ -1,68 +0,0 @@ -'\" -'\" Copyright (c) 1990-1994 The Regents of the University of California. -'\" Copyright (c) 1994-1996 Sun Microsystems, Inc. -'\" -'\" See the file "license.terms" for information on usage and redistribution -'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. -'\" -'\" RCS: @(#) $Id: bgerror.n,v 1.2 1998/09/14 18:39:51 stanton Exp $ -'\" -.so man.macros -.TH bgerror n 7.5 Tcl "Tcl Built-In Commands" -.BS -'\" Note: do not modify the .SH NAME line immediately below! -.SH NAME -bgerror \- Command invoked to process background errors -.SH SYNOPSIS -\fBbgerror \fImessage\fR -.BE - -.SH DESCRIPTION -.PP -The \fBbgerror\fR command doesn't exist as built-in part of Tcl. Instead, -individual applications or users can define a \fBbgerror\fR -command (e.g. as a Tcl procedure) if they wish to handle background -errors. -.PP -A background error is one that occurs in an event handler or some -other command that didn't originate with the application. -For example, if an error occurs while executing a command specified -with the \fBafter\fR command, then it is a background error. -For a non-background error, the error can simply be returned up -through nested Tcl command evaluations until it reaches the top-level -code in the application; then the application can report the error -in whatever way it wishes. -When a background error occurs, the unwinding ends in -the Tcl library and there is no obvious way for Tcl to report -the error. -.PP -When Tcl detects a background error, it saves information about the -error and invokes the \fBbgerror\fR command later as an idle event handler. -Before invoking \fBbgerror\fR, Tcl restores the \fBerrorInfo\fR -and \fBerrorCode\fR variables to their values at the time the -error occurred, then it invokes \fBbgerror\fR with -the error message as its only argument. -Tcl assumes that the application has implemented the \fBbgerror\fR -command, and that the command will report the error in a way that -makes sense for the application. Tcl will ignore any result returned -by the \fBbgerror\fR command as long as no error is generated. -.PP -If another Tcl error occurs within the \fBbgerror\fR command -(for example, because no \fBbgerror\fR command has been defined) -then Tcl reports the error itself by writing a message to stderr. -.PP -If several background errors accumulate before \fBbgerror\fR -is invoked to process them, \fBbgerror\fR will be invoked once -for each error, in the order they occurred. -However, if \fBbgerror\fR returns with a break exception, then -any remaining errors are skipped without calling \fBbgerror\fR. -.PP -Tcl has no default implementation for \fBbgerror\fR. -However, in applications using Tk there is a default -\fBbgerror\fR procedure -which posts a dialog box containing -the error message and offers the user a chance to see a stack -trace showing where the error occurred. - -.SH KEYWORDS -background error, reporting |