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Re: [PATCH doc/langref.tex] Add error probe information
On Thu, 3 Sep 2009, Josh Stone wrote:
On 09/03/2009 03:18 PM, Robb Romans wrote:
+\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. You can also numerically parametrize an \texttt{error}
+probe to set a sequence.
The meaning of the sequence isn't really clear until its described in
the next subsection for begin and end probes. Perhaps the error
sequence should be moved into that discussion?
It's similar to an end probe, which is why I put it immediately after that
probe. If you think it's clearer, I'll move it below "begin and end probe
sequence".
Here's a patch for that:
Signed-off-by: Robb Romans <robb@linux.vnet.ibm.com>
---
doc/langref.tex | 18 ++++++++++++++++++
1 files changed, 18 insertions(+), 0 deletions(-)
diff --git a/doc/langref.tex b/doc/langref.tex
index 3d08234..958e098 100644
--- a/doc/langref.tex
+++ b/doc/langref.tex
@@ -1053,6 +1053,24 @@ The user script \texttt{begin} probe defaults to sequence number zero, so
the tapset \texttt{begin} probe will run first.
+\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. You can also numerically parametrize an \texttt{error}
+probe to set a sequence.
+
+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{never}
\index{never}
The \texttt{never} probe point is defined by the translator to mean \emph{never}.
--
1.6.0.4
--
Robb Romans
IBM LTC Information Development
robb@linux.vnet.ibm.com