From 6379e59497c3d5e381cc5125461f0bbc51fd3e34 Mon Sep 17 00:00:00 2001
From: Jaana Burcu Dogan <jbd@google.com>
Date: Sun, 1 Jan 2017 19:54:15 -0800
Subject: [PATCH] Remove the -p flag.

Fixes #25.
---
 README.md | 17 +++++++++--------
 main.go   | 21 ++++++++++-----------
 2 files changed, 19 insertions(+), 19 deletions(-)

diff --git a/README.md b/README.md
index 52a72df..d6db599 100644
--- a/README.md
+++ b/README.md
@@ -47,6 +47,7 @@ func main() {
 #### 0. listing all processes
 
 To print all go processes, run `gops` without arguments:
+
 ```sh
 $ gops
 983     uplink-soecks	(/usr/local/bin/uplink-soecks)
@@ -62,8 +63,7 @@ Note that processes running the agent are marked with `*` next to the PID (e.g.
 In order to print the current stack trace from a target program, run the following command:
 
 ```sh
-$ gops stack -p=<PID>
-
+$ gops stack <pid>
 ```
 
 #### 2. memstats
@@ -71,7 +71,7 @@ $ gops stack -p=<PID>
 To print the current memory stats, run the following command:
 
 ```sh
-$ gops memstats -p=<PID>
+$ gops memstats <pid>
 ```
 
 #### 3. pprof
@@ -82,13 +82,13 @@ it shells out to the `go tool pprof` and let you interatively examine the profil
 To enter the CPU profile, run:
 
 ```sh
-$ gops pprof-cpu -p=<PID>
+$ gops pprof-cpu <pid>
 ```
 
 To enter the heap profile, run:
 
 ```sh
-$ gops pprof-heap -p=<PID>
+$ gops pprof-heap <pid>
 ```
 
 #### 4.  gc
@@ -97,7 +97,7 @@ If you want to force run garbage collection on the target program, run the follo
 It will block until the GC is completed.
 
 ```sh
-$ gops gc -p=<PID>
+$ gops gc <pid>
 ```
 
 #### 5. version
@@ -105,12 +105,13 @@ $ gops gc -p=<PID>
 gops reports the Go version the target program is built with, if you run the following:
 
 ```sh
-$ gops version -p=<PID>
+$ gops version <pid>
 ```
 
 #### 6. vitals
 
 To print the runtime statistics such as number of goroutines and `GOMAXPROCS`, run the following:
+
 ```sh
-$ gops vitals -p=<PID>
+$ gops vitals <pid>
 ```
diff --git a/main.go b/main.go
index 33af95f..7b3c7b9 100644
--- a/main.go
+++ b/main.go
@@ -6,10 +6,10 @@
 package main
 
 import (
-	"flag"
 	"fmt"
 	"log"
 	"os"
+	"strconv"
 	"strings"
 
 	"github.com/google/gops/internal/objfile"
@@ -19,8 +19,8 @@ import (
 
 const helpText = `Usage: gops is a tool to list and diagnose Go processes.
 
-    gops                  Lists all Go processes currently running.
-    gops [cmd] -p=<pid>   See the section below.
+    gops             Lists all Go processes currently running.
+    gops cmd <pid>   See the commands below.
 
 Commands:
     gc          Runs the garbage collector and blocks until successful.
@@ -50,18 +50,17 @@ func main() {
 	if cmd == "help" {
 		usage("")
 	}
+	if len(os.Args) < 3 {
+		usage("missing PID")
+	}
+	pid, err := strconv.Atoi(os.Args[2])
+	if err != nil {
+		usage("PID should be numeric")
+	}
 	fn, ok := cmds[cmd]
 	if !ok {
 		usage("unknown subcommand")
 	}
-
-	var pid int
-	flag.IntVar(&pid, "p", -1, "")
-	flag.CommandLine.Parse(os.Args[2:])
-	if pid == -1 {
-		usage("missing -p=<pid> flag")
-	}
-
 	if err := fn(pid); err != nil {
 		fmt.Fprintf(os.Stderr, "%v\n", err)
 		os.Exit(1)