From 4d0f6aeb9611900d7ee34075f921f3a707e8659d Mon Sep 17 00:00:00 2001
From: Trent Mick <trentm@gmail.com>
Date: Fri, 2 Nov 2012 12:15:29 -0700
Subject: [PATCH] ensure termination of child dtrace on CLI term by a signal

---
 CHANGES.md |  4 +++-
 bin/bunyan | 17 +++++++++++++++++
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/CHANGES.md b/CHANGES.md
index abc83db..b915820 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -2,7 +2,9 @@
 
 ## bunyan 0.16.1 (not yet released)
 
-(nothing yet)
+- Ensure that a possible dtrace child process (with using `bunyan -p PID`) is
+  terminated on signal termination of the bunyan CLI (at least for SIGINT,
+  SIGQUIT, SIGTERM, SIGHUP).
 
 
 ## bunyan 0.16.0
diff --git a/bin/bunyan b/bin/bunyan
index dfd58ba..61cf143 100755
--- a/bin/bunyan
+++ b/bin/bunyan
@@ -65,6 +65,9 @@ Object.keys(levelFromName).forEach(function (name) {
 // The current raw input line being processed. Used for `uncaughtException`.
 var currLine = null;
 
+// Child dtrace process, if any. Used for signal-handling.
+var child = null;
+
 
 
 //---- support functions
@@ -905,6 +908,7 @@ function processPid(opts, stylize, callback) {
   var argv = ['dtrace', '-Z', '-x', 'strsize=4k', '-qn',
     format('bunyan%d:::log-*{printf("%s", copyinstr(arg0))}', opts.pid)];
   var dtrace = spawn(argv[0], argv.slice(1));
+  child = dtrace; // intentionall global
 
   dtrace.stderr.pipe(process.stderr);
 
@@ -1023,6 +1027,19 @@ function asyncForEach(arr, iterator, callback) {
 
 //---- mainline
 
+// Try to ensure we close a child 'dtrace' process on signalled exit.
+function signalCleanupAndExit(signal) {
+  if (child) {
+    child.kill(signal);
+  }
+  process.exit();
+}
+process.on('SIGINT', function () { signalCleanupAndExit('SIGINT'); });
+process.on('SIGQUIT', function () { signalCleanupAndExit('SIGQUIT'); });
+process.on('SIGTERM', function () { signalCleanupAndExit('SIGTERM'); });
+process.on('SIGHUP', function () { signalCleanupAndExit('SIGHUP'); });
+
+
 process.on('uncaughtException', function (err) {
   function indent(s) {
     var lines = s.split(/\r?\n/);