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Re: [PATCH doc/langref.tex] Add error probe information
On Fri, 4 Sep 2009, Josh Stone wrote:
I only meant to merge the sequence bit with the other sequence info.
Right now it goes:
- begin
- end
- begin and end sequence
Your addition makes it:
- begin
- end
- error (mentioning but not explaining sequence)
- begin and end sequence
I'm just suggesting to make it more uniform:
- begin
- end
- error
- begin/end/error sequence
Sure, how's this?
Signed-off-by: Robb Romans <robb@linux.vnet.ibm.com>
---
doc/langref.tex | 35 +++++++++++++++++++++++++++--------
1 files changed, 27 insertions(+), 8 deletions(-)
diff --git a/doc/langref.tex b/doc/langref.tex
index 3d08234..eb5393b 100644
--- a/doc/langref.tex
+++ b/doc/langref.tex
@@ -1031,14 +1031,33 @@ of an \texttt{exit} function call, or an interruption from the user. In the
case of an shutdown triggered by error, \texttt{end} probes are not run.
-\subsubsection{begin and end probe sequence}
-\index{sequence}
-\texttt{begin} and \texttt{end} probes are specified with an optional sequence
-number that controls the order in which they are run. If no sequence number
-is provided, the sequence number defaults to zero and probes are run in the
-order that they occur in the script file. Sequence numbers may be either
-positive or negative, and are especially useful for tapset writers who want
-to do initialization in a \texttt{begin} probe. The following are examples.
+\subsubsection{error}
+\index{error}
+The \emph{error} probe point is similar to the end
+probe, except the probe handler runs when the session ends if an error
+occurred. In this case, an \texttt{end} probe is skipped, but each
+\texttt{error} probe is still attempted. You can use an
+\texttt{error} probe to clean up or perform a final action on script
+termination.
+
+Here is a simple example:
+\begin{vindent}
+\begin{verbatim}
+probe error { println ("Oops, errors occurred. Here's a report anyway.")
+ foreach (coin in mint) { println (coin) } }
+\end{verbatim}
+\end{vindent}
+
+
+\subsubsection{begin, end, and error probe sequence}
+\index{probe sequence}
+\texttt{begin}, \texttt{end}, and \texttt{error} probes can be
+specified with an optional sequence number that controls the order in
+which they are run. If no sequence number is provided, the sequence
+number defaults to zero and probes are run in the order that they
+occur in the script file. Sequence numbers may be either positive or
+negative, and are especially useful for tapset writers who want to do
+initialization in a \texttt{begin} probe. The following are examples.
\begin{vindent}
\begin{verbatim}
--
1.6.0.4
--
Robb Romans
IBM LTC Information Development
robb@linux.vnet.ibm.com