phier now uses getopts.

Old usage: phier 1234 sshd.
New usage: phier -s sshd 1234.

git-svn-id: https://svn.cambridge.iain.cx/profile/trunk@75 6be0d1a5-5cfe-0310-89b6-964be062b18b

diff --git a/phier b/phier
index f2aad9f..eaa1b14 100755 (executable)
--- a/phier
+++ b/phier
@@ -1,9 +1,23 @@
 #!/bin/bash
+#
+# $Id$
+#
+# phier: Show process tree incorporating a process.
+# Notes: phier functions similarly (but not identically) to Solaris ptree.
+# Usage: phier [options] <pid>
+# Options: -s <search>   Stop hierarchy at this process name.
+# Example: phier -s sshd $$
+#
 
 function find_parent() {
   child="$1"; shift
   top="$1"; shift
 
+  if [ -z "$child" ]; then
+    echo >&2 "No child to find."
+    return 1
+  fi
+
   cmd=$(ps -o comm= -p $child)
   pid=$(ps -o pid= -p $child)
   ppid=$(ps -o ppid= -p $child)
@@ -22,7 +36,7 @@ function find_parent() {
     fi
   fi
 
-  if [ $ppid = 1 ]; then
+  if [ $pid = 1 -o $ppid = 1 ]; then
     echo $pid
     return 0
   fi
@@ -31,16 +45,24 @@ function find_parent() {
   return $?
 }
 
+# Parse arguments.
+top=
+while getopts ":s:" opt; do
+  case $opt in
+    s) top="$1";;
+  esac
+done
+shift $((OPTIND-1))
+
 if [ $# -lt 1 ]; then
   echo >&2 "phier: Print process hierarchy for a process."
-  echo >&2 "Usage: phier <pid> [<search>]"
-  echo >&2 "Notes: If a search term is given the hierarchy will stop after finding a"
-  echo >&2 "       process matching that search term."
-  echo >&2 "Example: phier $$ sshd"
+  echo >&2 "Usage: phier [options] <pid>"
+  echo >&2 "Options: -s <search>   Stop hierarchy at this process name."
+  echo >&2 "Example: phier -s sshd $$"
   exit 1
 fi
 
-parent=$(find_parent ${1+"$@"})
+parent=$(find_parent "$1" "$top")
 if [ $? = 0 ]; then
   pstree -ulap $parent
 else