From c903f141890869a1a862deae4ad75413c7180107 Mon Sep 17 00:00:00 2001
From: Shannon Wynter <shannon.wynter@ladbrokes.com.au>
Date: Mon, 18 Apr 2016 11:15:15 +1000
Subject: [PATCH 1/3] Remove the requirement to use lsof by using the
 information provided in status to get the parent pid

---
 process/process.go       |  1 +
 process/process_linux.go | 46 ++++++++--------------------------------------
 2 files changed, 9 insertions(+), 38 deletions(-)

diff --git a/process/process.go b/process/process.go
index 2b9d685..4b69224 100644
--- a/process/process.go
+++ b/process/process.go
@@ -20,6 +20,7 @@ type Process struct {
 	Pid            int32 `json:"pid"`
 	name           string
 	status         string
+	parent         int32
 	numCtxSwitches *NumCtxSwitchesStat
 	uids           []int32
 	gids           []int32
diff --git a/process/process_linux.go b/process/process_linux.go
index e79ba36..4769047 100644
--- a/process/process_linux.go
+++ b/process/process_linux.go
@@ -6,10 +6,8 @@ import (
 	"bytes"
 	"encoding/json"
 	"errors"
-	"fmt"
 	"io/ioutil"
 	"os"
-	"os/exec"
 	"path/filepath"
 	"strconv"
 	"strings"
@@ -118,18 +116,11 @@ func (p *Process) Cwd() (string, error) {
 	return p.fillFromCwd()
 }
 func (p *Process) Parent() (*Process, error) {
-	r, err := callLsof("R", p.Pid)
-	if err != nil {
-		return nil, err
-	}
-	if len(r) != 1 { // TODO: pid 1
-		return nil, fmt.Errorf("wrong number of parents")
-	}
-	v, err := strconv.Atoi(r[0])
+	err := p.fillFromStatus()
 	if err != nil {
 		return nil, err
 	}
-	return NewProcess(int32(v))
+	return NewProcess(p.parent)
 }
 func (p *Process) Status() (string, error) {
 	err := p.fillFromStatus()
@@ -557,6 +548,12 @@ func (p *Process) fillFromStatus() error {
 			p.name = strings.Trim(value, " \t")
 		case "State":
 			p.status = value[0:1]
+		case "Ppid":
+			pval, err := strconv.ParseInt(value, 10, 32)
+			if err != nil {
+				return err
+			}
+			p.parent = int32(pval)
 		case "Uid":
 			p.uids = make([]int32, 0, 4)
 			for _, i := range strings.Split(value, "\t") {
@@ -704,30 +701,3 @@ func Pids() ([]int32, error) {
 
 	return ret, nil
 }
-
-func callLsof(arg string, pid int32) ([]string, error) {
-	var cmd []string
-	if pid == 0 { // will get from all processes.
-		cmd = []string{"-F" + arg}
-	} else {
-		cmd = []string{"-a", "-F" + arg, "-p", strconv.Itoa(int(pid))}
-	}
-	lsof, err := exec.LookPath("lsof")
-	if err != nil {
-		return []string{}, err
-	}
-	out, err := invoke.Command(lsof, cmd...)
-	if err != nil {
-		return []string{}, err
-	}
-	lines := strings.Split(string(out), "\n")
-
-	var ret []string
-	for _, l := range lines[1:] {
-		if strings.HasPrefix(l, arg) {
-			ret = append(ret, l[1:]) // delete first char
-		}
-	}
-
-	return ret, nil
-}

From a4387d0c9224018e208db958e53d387c833430c3 Mon Sep 17 00:00:00 2001
From: Shannon Wynter <shannon.wynter@ladbrokes.com.au>
Date: Mon, 18 Apr 2016 14:38:24 +1000
Subject: [PATCH 2/3] emulate original behaviour

---
 process/process_linux.go | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/process/process_linux.go b/process/process_linux.go
index 4769047..adc06d3 100644
--- a/process/process_linux.go
+++ b/process/process_linux.go
@@ -120,6 +120,9 @@ func (p *Process) Parent() (*Process, error) {
 	if err != nil {
 		return nil, err
 	}
+	if p.parent == 0 {
+		return nil, fmt.Errorf("wrong number of parents")
+	}
 	return NewProcess(p.parent)
 }
 func (p *Process) Status() (string, error) {

From f99d49546222d04b9be8405044b54299c5d89e3e Mon Sep 17 00:00:00 2001
From: Shannon Wynter <shannon.wynter@ladbrokes.com.au>
Date: Mon, 18 Apr 2016 17:28:47 +1000
Subject: [PATCH 3/3] Run goimports before committing...

---
 process/process_linux.go | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/process/process_linux.go b/process/process_linux.go
index adc06d3..75672a0 100644
--- a/process/process_linux.go
+++ b/process/process_linux.go
@@ -6,6 +6,7 @@ import (
 	"bytes"
 	"encoding/json"
 	"errors"
+	"fmt"
 	"io/ioutil"
 	"os"
 	"path/filepath"
@@ -551,7 +552,7 @@ func (p *Process) fillFromStatus() error {
 			p.name = strings.Trim(value, " \t")
 		case "State":
 			p.status = value[0:1]
-		case "Ppid":
+		case "PPid", "Ppid":
 			pval, err := strconv.ParseInt(value, 10, 32)
 			if err != nil {
 				return err