ImageView寬高時保持原比例

我只是要把一張bitmap放到App上置中秀出來, 並且可以保持原比例的放滿整個畫面.
為這樣子的功能Google了蠻久的, 因為總覺得不需要太複雜的設定, 就要可以達到這樣子的目的才對啊. 最後終於發現為什麼我一開始無法保持原比例放大了. 目前的結論如下:

layout的xml設定如下(它是一個LinearLayout 再加一個ImageView)

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_gravity="center"
    android:gravity="center" >
    <ImageView android:id="@+id/template_imageview"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        >
    </ImageView>
</LinearLayout>

android:layout_height="match_parent" <=== 很多人說要用"wrap_content"

然後在Java的程式裏面

ImageView imageView = (ImageView) findViewById(R.id.template_imageview);
imageView.setImageBitmap(downloadBitmap);
imageView.setAdjustViewBounds(true);

最重要的一行imageView.setAdjustViewBounds(true); 不設定為true的話無法放大圖片.

避免螢幕旋轉再次自動執行onCreate()

寫了一個程式, 裏面放了三個ListView, 依情況分別設定想要秀出來的ListView, 這時才發現, 當我旋轉手機後, 居然會重新呼叫onCreate(), 整個流程就從頭來過了.

查了一下官網的資料Handling The Change, 有教要如何避開這種情況. 主要是要做2個修正.
(1)AndroidManifest.xml (2)新增onConfigurationChanged

這兩個修改步驟如下:
(1)在AndroidManifest.xml裏面加入下圖, 紅色框框的文字.

新增的設定為android:configChanges="orientation|keyboardHidden|screenSize"

(2)在你的Activity.java檔案裏, 加入下面的程式碼

@Overridepublic void onConfigurationChanged(Configuration newConfig){
    super.onConfigurationChanged(newConfig);

}

根據實驗, 這樣子的修改後, 真的不會又被呼叫一次onCreate()了.

Modern C - Jens Gustedt

Jserv推廌的一本電子書, 由在 INRIA (法國國立電腦科學及自動化研究院) 任職的 Jens Gustedt 撰寫. 主要是探討新的 C 語言規格和應用規範.

Modern c from Stanley Ho

Resterization

發現一張好圖, 快速的說明了什麼是Resterization.

資料來源:
Android性能优化典范

行動上網速度比較表

紀錄一下這張表, 它顯示了各個規格的上/下載速度.

資料來源:
智慧型手機螢幕上方E、o、G、3G、H、H+、4G、4G+的意義

貨幣系統真相(Hidden Secrets of Money)

底下是由Mike Maloney所建立的一個以另類觀點去簡介現代金融的影片網站。目前共六集. https://www.hiddensecretsofmoney.com/
Currency vs. Money 通貨VS貨幣 第一集 (簡中版本)
Seven Stages of Empire 帝國的七個階段 第二集 (簡中版本)
From Dollar Crisis To Golden Opportunity 從美元危機到黃金機會 第三集 (簡體中文)
The Biggest Scam In The History Of Mankind (In 7 Easy Steps) 人類史上的最大騙局 第四集 中文
ULTIMATE HISTORY OF MONEY - Hidden Secrets Of Money Ep 5 - Mike Maloney 貨幣墮落引發的孿生險象 第五集 (簡體中文)
Rollercoaster Crash: Top 4 Reasons For Deflation - Hidden Secrets Of Money 6 (缺中文版)

數學函式操

動畫版:

via GIPHY

手繪版:

Audio Wave Format Specification

WAV File - Waveform Audio File Format (WAVE, or more commonly known as WAV due to its filename extension).
是微软與IBM公司所開發在個人電腦儲存音訊串流的編碼格式，它受到Windows平台的應用軟體之廣泛支援，也是使用者經常使用的指定規格之一。WAV音頻格式沒有經過壓縮(原則上只有在類比轉數位這個過程會失真)，所以音質不會出現失真的情況，但相對地，它的檔案體積在各種音頻格式中是比較大的。一般音樂CD片也是由WAV檔編輯而成。

Riffmci from Stanley Ho

底下的網頁講的也蠻不錯的
http://soundfile.sapp.org/doc/WaveFormat/

Little Endian注意事項:
裏面的Size存放格式都是Little Endian, 因此讀入後要轉換一下, 在fdk-aac的範例程式轉換函式入下:

static uint32_t read_int32(struct wav_reader* wr) {
        uint32_t value = 0;
        value |= fgetc(wr->wav) <<  0;
        value |= fgetc(wr->wav) <<  8;
        value |= fgetc(wr->wav) << 16;
        value |= fgetc(wr->wav) << 24;
        return value;
}

你也可以在include byteswap.h後使用bswap_32()函式

#include <stdio.h>
#include <stdlib.h>
#include <byteswap.h>

int main(int argc, char** argv){
        unsigned int a = 0x46000600;
        printf("%08x\n", bswap_32(a));
}

底下的範例檔案是使用ffmpeg將pcm資料轉成wav檔,整個wav檔的大小為778318bytes

52, 49, 46, 46代表"RIFF".
000be046代表扣掉目前的8個bytes後面的資料長度, 所以是778310+8=778318bytes.
57, 41 56, 45代表"WAVE".
66, 6d, 74, 20代表"fmt ".
00000010代表後面有接著16bytes的fmt資料(01 00 01 00 11 2b 00 00 22 56 00 00 02 00 10 00)
    0001 => Audio Format = 1(PCM)
    0001 => NumChannels = 1 channel
    00002b11 => 11025 Sample Rate
    00005622 => 22050 ByteRate
    0002 => BlockAlign = 2
    0010 => BitsPerSample = 16
4c, 49, 53, 54代表"LIST".
0000001a代表後面有接著26bytes的list資料(49 4e 46 4f 49 53 46 54 0e 00 00 00 4c 61 76 66 35 37 2e 31 39 2e 31 30 30 00)
64, 61, 74, 61代表"data".
000be000代表後面接著778240的資料. 所以778240+78=778318bytes

參考:
https://www.aelius.com/njh/wavemetatools/

英文月份的由來

一年有十二個月的英文名稱大都起源於拉丁文，有些更源自希臘、羅馬神話中的人物。

January 一月
取名自希臘、羅馬神話中的門神「Janus」，拉丁文為Ianuarius。他有兩副面孔，一張用來回顧過往，另一張則用來眺望未來，他也負責日出和日落，是象徵「開始」和「結束」之神。因此便取自他的名字，作為每年第一個月的名稱。我們可以在這個月回顧過去，展望新的一年。最初古羅馬曆法沒有這個月份。

February 二月
起源自古羅馬的「淨化節(Februa)」，拉丁文為Februarius，羅馬人民在每年二月初的節日—Februarius 都會宰殺牲畜、飲酒慶祝。在這一天，人們還用名叫 Februa 的一種牛與草混合製成的鞭子來抽打不孕的婦女，藉由此儀式讓該婦女能夠順利懷孕生子。這個拉丁文 Februarius 演變而成的 February來稱呼二月。最初古羅馬曆法沒有這個月份。

March 三月
本來是羅馬舊曆法當中一年的開始，也就是一月。之後由於凱撒大帝改革曆法，把這個月挪成了每年的第三個月。加上在羅馬的傳統中，出征打仗的時間都是在這個月，所以便沿用戰神 Mars 之名，稱三月為 Mars。古羅馬曆法的第一個月Martius。

April 四月
起源自「阿芙洛蒂特(Aphrodite)」，為希臘的愛神、美神、生育神，羅馬人將其轉化為「維納斯Venus」，四月是羅馬的春天，此時大地百花齊放、美不勝收，人們因此用拉丁文中的「開花的日子」（April）來代表四月。古羅馬曆法的第二個月Maius。

June 六月
起源自「朱諾(Juno)」，為羅馬神話中的天后，也是羅馬天神Jupiter的妻子，她也是一位保護女性的女神，負責婚姻，生育等工作，也因此六月是最適合結婚的月份，古羅馬曆法的第四個月Junius，是因為Juno在古羅馬有著十分崇高的地位，所以人們把六月奉獻給她，以她的名字來命名六月。

July 七月
原是古羅馬曆法的第五個月Quintilis，羅馬的朱里斯．凱撒大帝遇刺身亡後，將軍 Marcus Antonius 為紀念其宏偉事蹟，建議用他的名字 Julius 來命名其誕生的七月，因而取其名Gaius Julius Caesar中的Julius重新命名月份，

August 八月
原是古羅馬曆法的第六個月Sextilis，凱撒大帝死後，他的甥孫兼養子屋大維成為羅馬皇帝，為了表示跟凱撒一樣偉大，他也用自己的名字來命名月份。因為元老院在八月授予他「奧古斯都」（Augustus）的尊號，所以他決定將八月改成這個名稱。原來的八月比七月還少了一天，屋大維想跟凱撒平起平坐，決定從二月挪一天加到八月，讓八月跟七月都是三十一天。

September 九月
原是古羅馬曆法的第七個月September，拉丁文的7為septem。但是凱撒大帝改革曆法後，這一個月就變成了九月。

October 十月
原是古羅馬曆法的第八個月October，拉丁文的8為octo。人們在改革曆法後依舊習慣使用本來的稱呼，沿用到最後，英文十月就變成了 October。

November 十一月
原是古羅馬曆法的第九個月November，拉丁文的9為novem。羅馬皇帝奧古斯都和凱撒都有了自已名字命名的月份，羅馬市民和元老院要求當時的羅馬皇帝梯比里烏斯用他的名字命名11月，但梯比里烏斯沒有同意，他明智的對大家說，如果羅馬每個皇帝都用自己的名字來命名月份，那出現第十三個皇帝怎麼辦？因此十一月跟後來的九、十月一樣，使用舊有的名稱。

December 十二月
原是古羅馬曆法的第十個月December，拉丁文的10為decem。據說羅馬皇帝琉西烏斯要把一年中最後一個月用他的情婦Amagonius的名字來命名，但遭到元老院的反對。因此這個月在改革曆法後依舊被人們拿來稱呼十二月，使得 December 演變為英文的十二月。

資料來源: 網路到處搜集而來，可能有誤，當故事看看就好！

Android各個版本的使用狀況分析表

在Google的Android Dashboards頁面, 就有每個版本的使用率可以參考.
下圖是2015年11月份的狀況

Alsa Audio Capture

最近在試Camera Digital Microphone, 它基本上是走Alsa的架構,
因此找個Alsa Audio Capture的範例程式來做實驗.
參考資料來自於: Linux Journal Introduction to Sound Programming with ALSA

/*

   This example reads from the default PCM device
   and writes to standard output for 5 seconds of data.

 */

/* Use the newer ALSA API */
#define ALSA_PCM_NEW_HW_PARAMS_API

#include <alsa/asoundlib.h>

int main() {
        long loops;
        int rc;
        int size;
        snd_pcm_t *handle;
        snd_pcm_hw_params_t *params;
        unsigned int val;
        int dir;
        snd_pcm_uframes_t frames;
        char *buffer;

        /* Open PCM device for recording (capture). */
        rc = snd_pcm_open(&handle, "default", SND_PCM_STREAM_CAPTURE, 0);
        if (rc < 0) {
                fprintf(stderr, "unable to open pcm device: %s\n", snd_strerror(rc));
                exit(1);
        }

        /* Allocate a hardware parameters object. */
        snd_pcm_hw_params_alloca(&params);

        /* Fill it in with default values. */
        snd_pcm_hw_params_any(handle, params);

        /* Set the desired hardware parameters. */

        /* Interleaved mode */
        snd_pcm_hw_params_set_access(handle, params, SND_PCM_ACCESS_RW_INTERLEAVED);

        /* Signed 16-bit little-endian format */
        snd_pcm_hw_params_set_format(handle, params, SND_PCM_FORMAT_S16_LE);

        /* Two channels (stereo) */
        snd_pcm_hw_params_set_channels(handle, params, 2);

        /* 44100 bits/second sampling rate (CD quality) */
        val = 44100;
        snd_pcm_hw_params_set_rate_near(handle, params, &val, &dir);

        /* Set period size to 32 frames. */
        frames = 32;
        snd_pcm_hw_params_set_period_size_near(handle, params, &frames, &dir);

        /* Write the parameters to the driver */
        rc = snd_pcm_hw_params(handle, params);
        if (rc < 0) {
                fprintf(stderr, "unable to set hw parameters: %s\n", snd_strerror(rc));
                exit(1);
        }

        /* Use a buffer large enough to hold one period */
        snd_pcm_hw_params_get_period_size(params, &frames, &dir);
        size = frames * 4; /* 2 bytes/sample, 2 channels */
        buffer = (char *) malloc(size);

        /* We want to loop for 5 seconds */
        snd_pcm_hw_params_get_period_time(params, &val, &dir);
        loops = 5000000 / val;

        while (loops > 0) {
                loops--;
                rc = snd_pcm_readi(handle, buffer, frames);
                if (rc == -EPIPE) {
                        /* EPIPE means overrun */
                        fprintf(stderr, "overrun occurred\n");
                        snd_pcm_prepare(handle);
                } else if (rc < 0) {
                        fprintf(stderr, "error from read: %s\n", snd_strerror(rc));
                } else if (rc != (int)frames) {
                        fprintf(stderr, "short read, read %d frames\n", rc);
                }
                rc = write(1, buffer, size);
                if (rc != size)
                        fprintf(stderr, "short write: wrote %d bytes\n", rc);
        }

        snd_pcm_drain(handle);
        snd_pcm_close(handle);
        free(buffer);

        return 0;
}

目前錄出來的PCM聲音檔, 我是在ubuntu上用mplayer去播放
mplayer -rawaudio samplesize=2:channels=2:rate=11025 -demuxer rawaudio test.raw

使用ffmpeg將PCM檔轉WAV檔
ffmpeg -f s16le -ar 11025 -ac 2 -i ./test.pcm ./test.wav

• -f s16le … signed 16-bit little endian samples
• -ar 11025 … sample rate 11025Hz
• -ac 2 … 2 channels (stereo)
• -i test.pcm … input file
• test.wav … output file

在snd_pcm_readi這裏有遇到一個有趣的問題, 它回傳的值是audio frames的數量.
當你的資料是設定為16bits, 2 channles時, 一個frames的大小為4 bytes.

MPI Three-Group Pipeline

底下的MPI範例很有趣, 來自於5.6.3. Inter-Communication Examples
它主要是想要介紹建立三個節點, 彼此之間使用communicator串起來, 模擬成pipeline的運作方式.
希望產的效果如下圖:

程式碼我有動過, 如下

//http://www.mpi-forum.org/docs/mpi-1.1/mpi-11-html/node114.html
//Groups 0 and 1 communicate. Groups 1 and 2 communicate.
//Therefore, group 0 requires one inter-communicator, group 1 requires two inter-communicators,
//and group 2 requires 1 inter-communicator.

//int MPI_Comm_split(MPI_Comm comm, int color, int key, MPI_Comm *newcomm)
//int MPI_Intercomm_create(MPI_Comm local_comm, int local_leader, MPI_Comm peer_comm, int remote_leader, int tag, MPI_Comm *newintercomm)
#include <stdio.h>
#include <stdlib.h>
#include <mpi.h>
int main(int argc, char **argv){
        MPI_Comm   myComm;       /* intra-communicator of local sub-group */
        MPI_Comm   myFirstComm;  /* inter-communicator */
        MPI_Comm   mySecondComm; /* second inter-communicator (group 1 only) */
        int membershipKey = 0, rank =0, buffer = 0;
        MPI_Status status;
        double start_time, recive_time;

        MPI_Init(&argc, &argv);
        MPI_Comm_rank(MPI_COMM_WORLD, &rank);

        /* User code must generate membershipKey in the range [0, 1, 2] */
        membershipKey = rank % 3;
        start_time = MPI_Wtime();

        /* Build intra-communicator for local sub-group */
        MPI_Comm_split(MPI_COMM_WORLD, membershipKey, rank, &myComm);

        /* Build inter-communicators.  Tags are hard-coded. */
        if (membershipKey == 0){
                /* Group 0 communicates with group 1. */
                MPI_Intercomm_create( myComm, 0, MPI_COMM_WORLD, 1, 1, &myFirstComm);
        }
        else if (membershipKey == 1){
                /* Group 1 communicates with groups 0 and 2. */
                MPI_Intercomm_create( myComm, 0, MPI_COMM_WORLD, 0, 1, &myFirstComm);
                MPI_Intercomm_create( myComm, 0, MPI_COMM_WORLD, 2, 12, &mySecondComm);
        }
        else if (membershipKey == 2){
                /* Group 2 communicates with group 1. */
                MPI_Intercomm_create( myComm, 0, MPI_COMM_WORLD, 1, 12, &mySecondComm);
        }

        switch(membershipKey){
                case 0:
                        buffer = 100;
                        printf("[%d][%f]buffer=%d\n", rank, MPI_Wtime() - start_time, buffer);
                        MPI_Send(&buffer, 1, MPI_INT, 0, 0, myFirstComm);
                        MPI_Recv(&buffer, 1, MPI_INT, 0, 0, myFirstComm, &status);
                        printf("[%d][%f]buffer=%d\n", rank, MPI_Wtime() - start_time, buffer);
                        break;
                case 1:
                        printf("[%d][%f]buffer=%d\n", rank, MPI_Wtime() - start_time, buffer);
                        MPI_Recv(&buffer, 1, MPI_INT, 0, 0, myFirstComm, &status);
                        printf("[%d][%f]buffer=%d\n", rank, MPI_Wtime() - start_time, buffer);
                        buffer = 200;
                        MPI_Send(&buffer, 1, MPI_INT, 0, 0, myFirstComm);
                        MPI_Send(&buffer, 1, MPI_INT, 0, 0, mySecondComm);
                        break;
                case 2:
                        MPI_Recv(&buffer, 1, MPI_INT, 0, 0, mySecondComm, &status);
                        printf("[%d][%f]buffer=%d\n", rank, MPI_Wtime() - start_time, buffer);
                        break;
        }

        MPI_Comm_free(&myComm);
        switch(membershipKey){/* free communicators appropriately */
                case 1:
                        MPI_Comm_free(&mySecondComm);
                        MPI_Comm_free(&myFirstComm);
                        break;
                case 0:
                        MPI_Comm_free(&myFirstComm);
                        break;
                case 2:
                        MPI_Comm_free(&mySecondComm);
                        break;
        }
        MPI_Finalize();
}

執行的結果如下

Starting MPI_Init...
Starting MPI_Init...
Starting MPI_Init...
[0] Ending MPI_Init
[0] Starting MPI_Comm_rank...
[0] Ending MPI_Comm_rank
[0] Starting MPI_Comm_split...
[0] Ending MPI_Comm_split
[0] Starting MPI_Intercomm_create...
[0] Ending MPI_Intercomm_create
[0][0.000326]buffer=100
[0] Starting MPI_Send with count = 1, dest = 0, tag = 0...
[0] Ending MPI_Send
[0] Starting MPI_Recv with count = 1, source = 0, tag = 0...
[0] Ending MPI_Recv from 0 with tag 0
[0][0.000408]buffer=200
[0] Starting MPI_Comm_free...
[1] Ending MPI_Init
[1] Starting MPI_Comm_rank...
[1] Ending MPI_Comm_rank
[1] Starting MPI_Comm_split...
[1] Ending MPI_Comm_split
[1] Starting MPI_Intercomm_create...
[1] Ending MPI_Intercomm_create
[1] Starting MPI_Intercomm_create...
[1] Ending MPI_Intercomm_create
[1][0.000166]buffer=0
[1] Starting MPI_Recv with count = 1, source = 0, tag = 0...
[1] Ending MPI_Recv from 0 with tag 0
[1][0.000214]buffer=100
[1] Starting MPI_Send with count = 1, dest = 0, tag = 0...
[1] Ending MPI_Send
[1] Starting MPI_Send with count = 1, dest = 0, tag = 0...
[1] Ending MPI_Send
[1] Starting MPI_Comm_free...
[1] Ending MPI_Comm_free
[1] Starting MPI_Comm_free...
[2] Ending MPI_Init
[2] Starting MPI_Comm_rank...
[2] Ending MPI_Comm_rank
[2] Starting MPI_Comm_split...
[2] Ending MPI_Comm_split
[2] Starting MPI_Intercomm_create...
[2] Ending MPI_Intercomm_create
[0] Ending MPI_Comm_free
[0] Starting MPI_Comm_free...
[0] Ending MPI_Comm_free
[0] Starting MPI_Finalize...
[0] Ending MPI_Finalize
[1] Ending MPI_Comm_free
[1] Starting MPI_Comm_free...
[1] Ending MPI_Comm_free
[1] Starting MPI_Finalize...
[2] Starting MPI_Recv with count = 1, source = 0, tag = 0...
[2] Ending MPI_Recv from 0 with tag 0
[2][0.000409]buffer=200
[2] Starting MPI_Comm_free...
[2] Ending MPI_Comm_free
[2] Starting MPI_Comm_free...
[2] Ending MPI_Comm_free
[2] Starting MPI_Finalize...
[1] Ending MPI_Finalize
[2] Ending MPI_Finalize

改變vim程式碼註解的顏色

vim裏面程式碼註解的顏色預設值為深藍色.每次看註解都看到眼睛快花掉了.
還是改一下換個顏色.
vim ~/.vimrc
加入底下的命令
hi Comment ctermfg=cyan

效果如下圖:

你也可以試其它的顏色:

*cterm-colors*

NR-16   NR-8    COLOR NAME 
0       0       Black
1       4       DarkBlue
2       2       DarkGreen
3       6       DarkCyan
4       1       DarkRed
5       5       DarkMagenta
6       3       Brown, DarkYellow
7       7       LightGray, LightGrey, Gray, Grey
8       0*      DarkGray, DarkGrey
9       4*      Blue, LightBlue
10      2*      Green, LightGreen
11      6*      Cyan, LightCyan
12      1*      Red, LightRed
13      5*      Magenta, LightMagenta
14      3*      Yellow, LightYellow
15      7*      White

sscanf in C language

這個是Jack給的一個有趣程式, 以底下的範例來說
輸入的字串可是是"

#include <string.h>
#include <stdio.h>
int main(int argc, char** argv){
        int b[5] = {0, 0, 0, 0, 0};
        int ret;

        if(argc == 2){
                ret = sscanf( argv[1], "%d,%d,%d,%d,%d\n", &b[0], &b[1], &b[2], &b[3], &b[4]);
                printf("ret = %d, b0=%d b1=%d b2=%d b3=%d b4=%d\n", ret, b[0], b[1], b[2], b[3], b[4] );
        }
}

執行狀況如下:

./test

./test 1
ret = 1, b0=1 b1=0 b2=0 b3=0 b4=0

./test 1,2
ret = 2, b0=1 b1=2 b2=0 b3=0 b4=0

./test 1,2,3
ret = 3, b0=1 b1=2 b2=3 b3=0 b4=0

./test 1,2,3,4
ret = 4, b0=1 b1=2 b2=3 b3=4 b4=0

./test 1,2,3,4,5
ret = 5, b0=1 b1=2 b2=3 b3=4 b4=5

./test 1,2,3,4,5,6
ret = 5, b0=1 b1=2 b2=3 b3=4 b4=5

sscanf的函式宣告型態如下
int sscanf(const char *str, const char *format, ...);
使用它時需要

#include <stdio.h>

MPI_Bcast

MPI_Bcast廣播函式, 這個是一個很有趣的功能. 將要變更的資料變數及內容傳送給其它的接收

/* C Example */
#include <mpi.h>
#include <stdio.h>

int main (int argc, char* argv[]){
        int rank, size;
        double t1;
        void *v;
        int flag;
        int mytable[1] = { 0 };

        MPI_Init (&argc, &argv);      /* starts MPI */
        MPI_Comm_rank (MPI_COMM_WORLD, &rank);        /* get current process id */
        MPI_Comm_size (MPI_COMM_WORLD, &size);        /* get number of processes */
        t1 = MPI_Wtime();
        MPI_Attr_get( MPI_COMM_WORLD, MPI_WTIME_IS_GLOBAL, &v, &flag );
        printf( "Hello world from process %d of %d, time = %f, global time = %d\n", rank, size, MPI_Wtime() - t1, flag);

        mytable[0] = rank + 100;
        MPI_Barrier(MPI_COMM_WORLD);
        MPI_Bcast(&mytable[0], 1, MPI_INT, atoi(argv[1]), MPI_COMM_WORLD);
        printf("%d/%d: mytable[0] = %d\n", rank, size, mytable[0]);
        MPI_Barrier(MPI_COMM_WORLD);

        MPI_Finalize();
        return 0;
}

mpirun -np 5 ./bcast 0執行結果1

Starting MPI_Init...
Starting MPI_Init...
Starting MPI_Init...
Starting MPI_Init...
Starting MPI_Init...
[0] Ending MPI_Init
[0] Starting MPI_Comm_rank...
[0] Ending MPI_Comm_rank
[0] Starting MPI_Comm_size...
[0] Ending MPI_Comm_size
[0] Starting MPI_Attr_get...
[0] Ending MPI_Attr_get
Hello world from process 0 of 5, time = 0.000011, global time = 1
[0] Starting MPI_Barrier...
[0] Ending MPI_Barrier
[0] Starting MPI_Bcast...
[0] Starting MPI_Bcast with count = 1
[0] Ending MPI_Bcast
0/5: mytable[0] = 100
[0] Starting MPI_Barrier...
[0] Ending MPI_Barrier
[0] Starting MPI_Finalize...
[0] Ending MPI_Finalize
[1] Ending MPI_Init
[1] Starting MPI_Comm_rank...
[1] Ending MPI_Comm_rank
[1] Starting MPI_Comm_size...
[1] Ending MPI_Comm_size
[1] Starting MPI_Attr_get...
[1] Ending MPI_Attr_get
Hello world from process 1 of 5, time = 0.000012, global time = 1
[1] Starting MPI_Barrier...
[1] Ending MPI_Barrier
[1] Starting MPI_Bcast...
[1] Starting MPI_Bcast with count = 1
[1] Ending MPI_Bcast
1/5: mytable[0] = 100
[1] Starting MPI_Barrier...
[1] Ending MPI_Barrier
[1] Starting MPI_Finalize...
[1] Ending MPI_Finalize
[2] Ending MPI_Init
[2] Starting MPI_Comm_rank...
[2] Ending MPI_Comm_rank
[2] Starting MPI_Comm_size...
[2] Ending MPI_Comm_size
[2] Starting MPI_Attr_get...
[2] Ending MPI_Attr_get
Hello world from process 2 of 5, time = 0.000012, global time = 1
[2] Starting MPI_Barrier...
[2] Ending MPI_Barrier
[2] Starting MPI_Bcast...
[2] Starting MPI_Bcast with count = 1
[2] Ending MPI_Bcast
2/5: mytable[0] = 100
[2] Starting MPI_Barrier...
[2] Ending MPI_Barrier
[2] Starting MPI_Finalize...
[3] Ending MPI_Init
[3] Starting MPI_Comm_rank...
[3] Ending MPI_Comm_rank
[3] Starting MPI_Comm_size...
[3] Ending MPI_Comm_size
[3] Starting MPI_Attr_get...
[3] Ending MPI_Attr_get
Hello world from process 3 of 5, time = 0.000010, global time = 1
[3] Starting MPI_Barrier...
[3] Ending MPI_Barrier
[3] Starting MPI_Bcast...
[3] Starting MPI_Bcast with count = 1
[3] Ending MPI_Bcast
3/5: mytable[0] = 100
[3] Starting MPI_Barrier...
[3] Ending MPI_Barrier
[3] Starting MPI_Finalize...
[4] Ending MPI_Init
[4] Starting MPI_Comm_rank...
[4] Ending MPI_Comm_rank
[4] Starting MPI_Comm_size...
[4] Ending MPI_Comm_size
[4] Starting MPI_Attr_get...
[4] Ending MPI_Attr_get
Hello world from process 4 of 5, time = 0.000009, global time = 1
[4] Starting MPI_Barrier...
[4] Ending MPI_Barrier
[4] Starting MPI_Bcast...
[4] Starting MPI_Bcast with count = 1
[4] Ending MPI_Bcast
4/5: mytable[0] = 100
[4] Starting MPI_Barrier...
[4] Ending MPI_Barrier
[4] Starting MPI_Finalize...
[2] Ending MPI_Finalize
[3] Ending MPI_Finalize
[4] Ending MPI_Finalize

mpirun -np 5 ./bcast 1執行結果2

Starting MPI_Init...
Starting MPI_Init...
Starting MPI_Init...
Starting MPI_Init...
Starting MPI_Init...
[0] Ending MPI_Init
[0] Starting MPI_Comm_rank...
[0] Ending MPI_Comm_rank
[0] Starting MPI_Comm_size...
[0] Ending MPI_Comm_size
[0] Starting MPI_Attr_get...
[0] Ending MPI_Attr_get
Hello world from process 0 of 5, time = 0.000017, global time = 1
[0] Starting MPI_Barrier...
[0] Ending MPI_Barrier
[0] Starting MPI_Bcast...
[0] Starting MPI_Bcast with count = 1
[0] Ending MPI_Bcast
0/5: mytable[0] = 101
[0] Starting MPI_Barrier...
[0] Ending MPI_Barrier
[0] Starting MPI_Finalize...
[1] Ending MPI_Init
[1] Starting MPI_Comm_rank...
[1] Ending MPI_Comm_rank
[1] Starting MPI_Comm_size...
[1] Ending MPI_Comm_size
[1] Starting MPI_Attr_get...
[1] Ending MPI_Attr_get
Hello world from process 1 of 5, time = 0.000010, global time = 1
[1] Starting MPI_Barrier...
[1] Ending MPI_Barrier
[1] Starting MPI_Bcast...
[1] Starting MPI_Bcast with count = 1
[1] Ending MPI_Bcast
1/5: mytable[0] = 101
[1] Starting MPI_Barrier...
[1] Ending MPI_Barrier
[1] Starting MPI_Finalize...
[1] Ending MPI_Finalize
[2] Ending MPI_Init
[2] Starting MPI_Comm_rank...
[2] Ending MPI_Comm_rank
[2] Starting MPI_Comm_size...
[2] Ending MPI_Comm_size
[2] Starting MPI_Attr_get...
[2] Ending MPI_Attr_get
Hello world from process 2 of 5, time = 0.000008, global time = 1
[2] Starting MPI_Barrier...
[2] Ending MPI_Barrier
[2] Starting MPI_Bcast...
[2] Starting MPI_Bcast with count = 1
[2] Ending MPI_Bcast
2/5: mytable[0] = 101
[2] Starting MPI_Barrier...
[2] Ending MPI_Barrier
[2] Starting MPI_Finalize...
[3] Ending MPI_Init
[3] Starting MPI_Comm_rank...
[3] Ending MPI_Comm_rank
[3] Starting MPI_Comm_size...
[3] Ending MPI_Comm_size
[3] Starting MPI_Attr_get...
[3] Ending MPI_Attr_get
Hello world from process 3 of 5, time = 0.000008, global time = 1
[3] Starting MPI_Barrier...
[3] Ending MPI_Barrier
[3] Starting MPI_Bcast...
[3] Starting MPI_Bcast with count = 1
[3] Ending MPI_Bcast
3/5: mytable[0] = 101
[3] Starting MPI_Barrier...
[3] Ending MPI_Barrier
[3] Starting MPI_Finalize...
[4] Ending MPI_Init
[4] Starting MPI_Comm_rank...
[4] Ending MPI_Comm_rank
[4] Starting MPI_Comm_size...
[4] Ending MPI_Comm_size
[4] Starting MPI_Attr_get...
[4] Ending MPI_Attr_get
Hello world from process 4 of 5, time = 0.000009, global time = 1
[4] Starting MPI_Barrier...
[4] Ending MPI_Barrier
[4] Starting MPI_Bcast...
[4] Starting MPI_Bcast with count = 1
[4] Ending MPI_Bcast
4/5: mytable[0] = 101
[4] Starting MPI_Barrier...
[4] Ending MPI_Barrier
[4] Starting MPI_Finalize...
[0] Ending MPI_Finalize
[2] Ending MPI_Finalize
[3] Ending MPI_Finalize
[4] Ending MPI_Finalize

MPI_Wtime

突然發現, 原來MPI有提供一個函式MPI_Wtime(), 可以用來計算運行過的時間, 單位是秒.
它的回傳值是double, 並且需要確定你的系統環境是MPI_WTIME_IS_GLOBAL是有被定義的.

/* C Example */
#include <mpi.h>
#include <stdio.h>

int main (int argc, char* argv[]){
        int rank, size;
        double t1;
        void *v;
        int flag;

        MPI_Init (&argc, &argv);      /* starts MPI */
        MPI_Comm_rank (MPI_COMM_WORLD, &rank);        /* get current process id */
        MPI_Comm_size (MPI_COMM_WORLD, &size);        /* get number of processes */
        t1 = MPI_Wtime();
        MPI_Attr_get( MPI_COMM_WORLD, MPI_WTIME_IS_GLOBAL, &v, &flag );
        printf( "Hello world from process %d of %d, time = %f, global time = %d\n", rank, size, MPI_Wtime() - t1, flag);
        MPI_Finalize();
        return 0;
}

MPI & MPE Helloworld

這次來介紹MPI搭配MPE(MPI Parallel Environment)來tracing程式的運作
主程式hello.c跟先前的相同, 程式碼如下:

/* C Example */
#include <mpi.h>
#include <stdio.h>

int main (int argc, char* argv[])
{
  int rank, size;

  MPI_Init (&argc, &argv);      /* starts MPI */
  MPI_Comm_rank (MPI_COMM_WORLD, &rank);        /* get current process id */
  MPI_Comm_size (MPI_COMM_WORLD, &size);        /* get number of processes */
  printf( "Hello world from process %d of %d\n", rank, size );
  MPI_Finalize();
  return 0;
}

Makefile內容如下:

all:
        mpecc -mpitrace -o hello hello.c

mpirun -np 5 ./hello 執行的結果如下:

Starting MPI_Init...
Starting MPI_Init...
Starting MPI_Init...
Starting MPI_Init...
Starting MPI_Init...
[0] Ending MPI_Init
[0] Starting MPI_Comm_rank...
[0] Ending MPI_Comm_rank
[0] Starting MPI_Comm_size...
[0] Ending MPI_Comm_size
Hello world from process 0 of 5
[0] Starting MPI_Finalize...
[0] Ending MPI_Finalize
[1] Ending MPI_Init
[1] Starting MPI_Comm_rank...
[1] Ending MPI_Comm_rank
[1] Starting MPI_Comm_size...
[1] Ending MPI_Comm_size
Hello world from process 1 of 5
[1] Starting MPI_Finalize...
[1] Ending MPI_Finalize
[2] Ending MPI_Init
[2] Starting MPI_Comm_rank...
[2] Ending MPI_Comm_rank
[2] Starting MPI_Comm_size...
[2] Ending MPI_Comm_size
Hello world from process 2 of 5
[2] Starting MPI_Finalize...
[3] Ending MPI_Init
[3] Starting MPI_Comm_rank...
[3] Ending MPI_Comm_rank
[3] Starting MPI_Comm_size...
[3] Ending MPI_Comm_size
Hello world from process 3 of 5
[3] Starting MPI_Finalize...
[4] Ending MPI_Init
[4] Starting MPI_Comm_rank...
[4] Ending MPI_Comm_rank
[4] Starting MPI_Comm_size...
[4] Ending MPI_Comm_size
Hello world from process 4 of 5
[4] Starting MPI_Finalize...
[2] Ending MPI_Finalize
[3] Ending MPI_Finalize
[4] Ending MPI_Finalize

Brillo Toybox

大概瞄了一下, 突然發現, system/bin/裏面不是裝busybox也不是裝toolbox了.改成用toybox了.
原來AOSP已經改用toybox了, 看起來這轉換的過程也歷經了許多的故事.
有興趣的可以看一下Android gets a toybox.

底下這張圖是brillo裏/system/bin的檔案列表.

.
├── bin
│   ├── acpi -> toybox
│   ├── apmanager
│   ├── applypatch_static
│   ├── audio_hal_playback_test
│   ├── audio_hal_record_test
│   ├── avahi-browse
│   ├── avahi-daemon
│   ├── base64 -> toybox
│   ├── basename -> toybox
│   ├── bdt
│   ├── blockdev -> toybox
│   ├── bluetooth-cli
│   ├── bluetoothtbd
│   ├── bootctl
│   ├── brillo_audio_test
│   ├── bzcat -> toybox
│   ├── cal -> toybox
│   ├── cat -> toybox
│   ├── chcon -> toybox
│   ├── check_prereq
│   ├── chgrp -> toybox
│   ├── chmod -> toybox
│   ├── chown -> toybox
│   ├── chroot -> toybox
│   ├── cjpeg
│   ├── cksum -> toybox
│   ├── clear -> toybox
│   ├── cmp -> toybox
│   ├── comm -> toybox
│   ├── core2md
│   ├── cp -> toybox
│   ├── cpio -> toybox
│   ├── crash_reporter
│   ├── crash_sender
│   ├── curl
│   ├── cut -> toybox
│   ├── date -> toybox
│   ├── dbus-daemon
│   ├── dbus-example-client
│   ├── dbus-example-daemon
│   ├── dbus-send
│   ├── dd -> toolbox
│   ├── df -> toybox
│   ├── dhcpcd
│   ├── dhcpcd-6.8.2
│   ├── dhcptool
│   ├── dirname -> toybox
│   ├── djpeg
│   ├── dmesg -> toybox
│   ├── dnsmasq
│   ├── dos2unix -> toybox
│   ├── du -> toybox
│   ├── echo -> toybox
│   ├── egrep -> grep
│   ├── env -> toybox
│   ├── expand -> toybox
│   ├── expr -> toybox
│   ├── fallocate -> toybox
│   ├── false -> toybox
│   ├── ff_debug
│   ├── fgrep -> grep
│   ├── find -> toybox
│   ├── firewalld
│   ├── flash_image
│   ├── flock -> toybox
│   ├── free -> toybox
│   ├── gdbserver
│   ├── getenforce -> toybox
│   ├── getevent -> toolbox
│   ├── getprop -> toybox
│   ├── grep
│   ├── groups -> toybox
│   ├── head -> toybox
│   ├── hostapd
│   ├── hostapd_cli
│   ├── hostname -> toybox
│   ├── hwclock -> toybox
│   ├── id -> toybox
│   ├── ifconfig -> toybox
│   ├── iftop -> toolbox
│   ├── initnetwork.sh
│   ├── inotifyd -> toybox
│   ├── insmod -> toybox
│   ├── ioctl -> toolbox
│   ├── ionice -> toybox
│   ├── iorenice -> toybox
│   ├── iotop
│   ├── ip
│   ├── ip6tables
│   ├── ip6tables-restore -> ip6tables
│   ├── ip6tables-save -> ip6tables
│   ├── iptables
│   ├── iptables-restore -> iptables
│   ├── iptables-save -> iptables
│   ├── iw
│   ├── keystore
│   ├── keystore_cli
│   ├── keystore_cli_v2
│   ├── kill -> toybox
│   ├── killall -> toybox
│   ├── linker
│   ├── ln -> toybox
│   ├── load_policy -> toybox
│   ├── log -> toolbox
│   ├── logcat
│   ├── logd
│   ├── logname -> toybox
│   ├── logpersist.cat -> logpersist.start
│   ├── logpersist.start
│   ├── logpersist.stop -> logpersist.start
│   ├── losetup -> toybox
│   ├── ls -> toybox
│   ├── lsmod -> toybox
│   ├── lsof -> toybox
│   ├── lsusb -> toybox
│   ├── md5sum -> toybox
│   ├── mediaserver
│   ├── memory_replay32
│   ├── metrics_client
│   ├── metrics_daemon
│   ├── mkdir -> toybox
│   ├── mknod -> toybox
│   ├── mkswap -> toybox
│   ├── mktemp -> toybox
│   ├── modinfo -> toybox
│   ├── more -> toybox
│   ├── mount -> toybox
│   ├── mountpoint -> toybox
│   ├── mv -> toybox
│   ├── nandread -> toolbox
│   ├── nativepowerman
│   ├── netstat -> toybox
│   ├── newfs_msdos -> toolbox
│   ├── nice -> toybox
│   ├── nl -> toybox
│   ├── nohup -> toybox
│   ├── od -> toybox
│   ├── paste -> toybox
│   ├── patch -> toybox
│   ├── periodic_scheduler
│   ├── pgrep -> toybox
│   ├── pidof -> toybox
│   ├── ping
│   ├── pkill -> toybox
│   ├── pmap -> toybox
│   ├── postinst_example
│   ├── power_example
│   ├── printenv -> toybox
│   ├── printf -> toybox
│   ├── prlimit -> toolbox
│   ├── ps -> toolbox
│   ├── pwd -> toybox
│   ├── r
│   ├── readlink -> toybox
│   ├── realpath -> toybox
│   ├── reboot
│   ├── renice -> toybox
│   ├── restorecon -> toybox
│   ├── rm -> toybox
│   ├── rmdir -> toybox
│   ├── rmmod -> toybox
│   ├── rootdev
│   ├── route -> toybox
│   ├── runcon -> toybox
│   ├── sed -> toybox
│   ├── sendevent -> toolbox
│   ├── sensorservice
│   ├── sensors-hal-example-app
│   ├── sensors-ndk-example-app
│   ├── seq -> toybox
│   ├── servicemanager
│   ├── setenforce -> toybox
│   ├── setprop -> toybox
│   ├── setsid -> toybox
│   ├── sh
│   ├── sha1sum -> toybox
│   ├── shill
│   ├── showlease
│   ├── sleep -> toybox
│   ├── slesTest_playFdPath
│   ├── slesTest_recBuffQueue
│   ├── slesTest_sawtoothBufferQueue
│   ├── sort -> toybox
│   ├── split -> toybox
│   ├── start -> toolbox
│   ├── stat -> toybox
│   ├── stop -> toolbox
│   ├── strings -> toybox
│   ├── swapoff -> toybox
│   ├── swapon -> toybox
│   ├── sync -> toybox
│   ├── sysctl -> toybox
│   ├── tac -> toybox
│   ├── tail -> toybox
│   ├── tar -> toybox
│   ├── taskset -> toybox
│   ├── tee -> toybox
│   ├── time -> toybox
│   ├── timeout -> toybox
│   ├── tlsdate
│   ├── tlsdated
│   ├── tlsdate-helper
│   ├── toolbox
│   ├── top -> toolbox
│   ├── touch -> toybox
│   ├── toybox
│   ├── tr -> toybox
│   ├── tracepath
│   ├── tracepath6
│   ├── traceroute6
│   ├── true -> toybox
│   ├── truncate -> toybox
│   ├── tty -> toybox
│   ├── umount -> toybox
│   ├── uname -> toybox
│   ├── uniq -> toybox
│   ├── unix2dos -> toybox
│   ├── update_engine
│   ├── update_engine_client
│   ├── updater
│   ├── uptime -> toybox
│   ├── usleep -> toybox
│   ├── vmstat -> toybox
│   ├── wc -> toybox
│   ├── weaved
│   ├── webservd
│   ├── which -> toybox
│   ├── whoami -> toybox
│   ├── wifi_init
│   ├── wpa_cli
│   ├── wpa_debug
│   ├── wpa_supplicant
│   ├── xargs -> toybox
│   ├── xxd -> toybox
│   └── yes -> toybox

宅色夫大大的 - 你所不知道的C語言beta 11/23 指標篇

你所不知道的C語言 : 指標篇



Andrew Koenig - C Traps and Pitfalls
Interactive compiler - http://gcc.godbolt.org/ , 沒有MIPS有點可惜.

Ubuntu vs VNC

實驗室的Server一向都是裝沒有桌面環境的, 結果最近要跑的一個qemu居然會啟vnc起來.
只好隨便裝一下.
狀況真的有點慘烈, vncview連上去, 很醜. 只能將就點用了, 懶的再改了.
記錄一下目前的.vnc/xstartup裏面的設定.

 cat xstartup
#!/bin/sh
export XKL_XMODMAP_DISABLE=1
unset SESSION_MANAGER
unset DBUS_SESSION_BUS_ADDRESS

gnome-panel &
gnome-settings-daemon &
metacity &
nautilus &
gnome-terminal &

底下是vncviewer連上去的畫面.

我原本的認知, 應該是要能直接用gnome-session跑window的環境的, 但居然報出底下的訊息.
也有用過gnome-session --session=ubuntu-2d去試過, 基本沒狀況相同.

 gnome-session
gnome-session-is-accelerated: No composite extension.
gnome-session-check-accelerated: Helper exited with code 256
gnome-session-is-accelerated: No composite extension.
gnome-session-check-accelerated: Helper exited with code 256
gnome-session[9150]: WARNING: software acceleration check failed: Child process exited with code 1
gnome-session[9150]: CRITICAL: We failed, but the fail whale is dead. Sorry....

1.GNOME Panel - 主要負責程式啟動清單以及工作列的功能.
2.gnome-settings-daemon - daemon handling the GNOME session settings
3.metacity - 視窗管理程式
4.nautilus - gnome的檔案瀏覽器
5.gnome-terminal - 就終端機程式

Google IoT Soluation - Brillo Project

如果不知道Google Brillo是什麼, 可以考慮看一下底下的兩段影片
(1)Google I/O 2015 Keynote 完整紀錄

(2)Brillo官網上的An Introduction to Brillo, the OS for IoT

根據TechOrange科技報橘 沈孟學 - 【年度祭典！Google I/O 現場報導】Google 物聯網平台 Brillo 來了，能讓物體「溝通」更智慧嗎？ 裏面, 也是摘錄自Google I/O的簡介, 說了, 使用Brillo作業系統裝置的三大特性.
·智慧：不管使用者是從辦公室回家、或是周末悠閒待在家裡，運行 Brillo 作業系統的裝置都能做出準確的反應，讓使用者享有便捷、智慧的使用體驗。此外，輕鬆分享讓使用者可以提供客人一個專用的暫時性無線網路，或是暫停已啟用的 Smart Lock。

·簡單：Brillo 的啟用設定相當簡單，而且每一台 Android 裝置都有內建自動偵測。「Android On」應用程式可以協助使用者將所有裝置連線，在一個地方功能即可輕鬆、簡單地管理所有的裝置。

·同步：使用者不會被限制於某一品牌的裝置，只要是搭載「Android On」應用未來在例如 Nest 或 Homekit 等其他平台的裝置也將能運作程式的裝置皆可順暢運作。

另外還有一個名詞要注意: Weave - 簡單說就是Brillo Device之間溝通的protocol.

在官方的說法, Brillo的硬體需求為32MB的記憶體, 128M的系統儲存空間, 老實講這樣子的需求對IoT裝置來說, 太高了吧!

因為Brillo已經Release出來了, 當然就要抓下來看看長的是圓是扁囉!
底下的過程我也是參考How to Build Brillo Operating System from Source Code and Run Brillo Emulator


步驟1:
下載Brillo Source Code, 這裏是針對branch brillo-m7-release下載

repo init -u https://android.googlesource.com/brillo/manifest -b brillo-m7-release

步驟2:
設定編譯環境

source build/envsetup.sh

會看到底下的訊息

including device/generic/brillo/vendorsetup.sh
including device/generic/brillo/brilloemulator_arm64/base_product/devicesetup.sh
including device/generic/brillo/brilloemulator_arm/base_product/devicesetup.sh
including device/generic/brillo/brilloemulator_x86_64/base_product/devicesetup.s                                                       h
including device/generic/brillo/brilloemulator_x86/base_product/devicesetup.sh
including device/generic/mini-emulator-arm64/vendorsetup.sh
including device/generic/mini-emulator-armv7-a-neon/vendorsetup.sh
including device/generic/mini-emulator-x86_64/vendorsetup.sh
including device/generic/mini-emulator-x86/vendorsetup.sh
including product/google/common/brillo_gpios/vendorsetup.sh
including product/google/common/brillo_leds/vendorsetup.sh
including product/google/example-ledflasher/vendorsetup.sh

步驟3:
選擇編譯的目標平台

launch

會看到底下的訊息, 在which would you like的地方輸入10, 指定要編譯的目標平台為brilloemulator_x86-eng, 選9的話會編譯錯誤

You're building on Linux

Lunch menu... pick a combo:
     1. aosp_arm-eng
     2. aosp_arm64-eng
     3. aosp_mips-eng
     4. aosp_mips64-eng
     5. aosp_x86-eng
     6. aosp_x86_64-eng
     7. brilloemulator_arm64-eng
     8. brilloemulator_arm-eng
     9. brilloemulator_x86_64-eng
     10. brilloemulator_x86-eng
     11. mini_emulator_arm64-userdebug
     12. m_e_arm-userdebug
     13. mini_emulator_x86_64-userdebug
     14. mini_emulator_x86-userdebug
     15. brillo_gpios-userdebug
     16. brillo_leds-userdebug
     17. ledflasher-userdebug

Which would you like? [aosp_arm-eng] 10

============================================
PLATFORM_VERSION_CODENAME=REL
PLATFORM_VERSION=6.0.60
TARGET_PRODUCT=brilloemulator_x86
TARGET_BUILD_VARIANT=eng
TARGET_BUILD_TYPE=release
TARGET_BUILD_APPS=
TARGET_ARCH=x86
TARGET_ARCH_VARIANT=x86
TARGET_CPU_VARIANT=
TARGET_2ND_ARCH=
TARGET_2ND_ARCH_VARIANT=
TARGET_2ND_CPU_VARIANT=
HOST_ARCH=x86_64
HOST_OS=linux
HOST_OS_EXTRA=Linux-3.13.0-24-generic-x86_64-with-Ubuntu-14.04-trusty
HOST_CROSS_OS=windows
HOST_BUILD_TYPE=release
BUILD_ID=MASTER
OUT_DIR=out
============================================

步驟4:
開始編譯brillo

make -j20

如果你的編譯環境都是正常的話, 就會看到底下的結果

make_ext4fs -T -1 -S out/target/product/brilloemulator_x86/root/file_contexts.bin -L / -l 786432000 -a / out/target/product/brilloemulator_x86/obj/PACKAGING/systemimage_intermediates/system.img /tmp/tmpceM3H7 out/target/product/brilloemulator_x86/system
Creating filesystem with parameters:
    Size: 786432000
    Block size: 4096
    Blocks per group: 32768
    Inodes per group: 8000
    Inode size: 256
    Journal blocks: 3000
    Label: /
    Blocks: 192000
    Block groups: 6
    Reserved block group size: 47
Created filesystem with 691/48000 inodes and 30669/192000 blocks
[100% 8493/8493] Install system fs image: out/target/product/brilloemulator_x86/system.img
out/target/product/brilloemulator_x86/system.img+out/target/product/brilloemulator_x86/recovery.img maxsize=802897920 blocksize=2112 total=793747456 reserve=8110080

#### make completed successfully (04:31 (mm:ss)) ####

步驟5:
執行brillo的模擬器

./out/host/linux-x86/bin/brilloemulator-x86

接著它就會開始跑模擬器, 並且看到整個開機過程, 最後進入terminal的畫面

Starting Emulator with 1024MB Memory
pulseaudio: pa_context_connect() failed
pulseaudio: Reason: Connection refused
pulseaudio: Failed to initialize PA contextaudio: Could not init `pa' audio driver
adb_server_notify: Failed to establish connection to ADB server
console on port 5556, ADB on port 5557
[    0.000000] Initializing cgroup subsys cpuset
[    0.000000] Initializing cgroup subsys cpu
[    0.000000] Initializing cgroup subsys cpuacct
[    0.000000] Linux version 3.18.0+ (stanley@ubuntu-core40) (gcc version 4.9 20140827 (prerelease) (GCC) ) #1 SMP Tue Nov 24 21:27:40 CST 2015
[    0.000000] e820: BIOS-provided physical RAM map:
[    0.000000] BIOS-e820: [mem 0x0000000000000000-0x000000000009fbff] usable
[    0.000000] BIOS-e820: [mem 0x000000000009fc00-0x000000000009ffff] reserved
[    0.000000] BIOS-e820: [mem 0x00000000000f0000-0x00000000000fffff] reserved
[    0.000000] BIOS-e820: [mem 0x0000000000100000-0x000000003ffdffff] usable
[    0.000000] BIOS-e820: [mem 0x000000003ffe0000-0x000000003fffffff] reserved
[    0.000000] BIOS-e820: [mem 0x00000000fffc0000-0x00000000ffffffff] reserved
[    0.000000] Notice: NX (Execute Disable) protection missing in CPU!
[    0.000000] SMBIOS 2.8 present.
[    0.000000] e820: last_pfn = 0x3ffe0 max_arch_pfn = 0x1000000
[    0.000000] found SMP MP-table at [mem 0x000f0e90-0x000f0e9f] mapped at [c00f0e90]
[    0.000000] Scanning 1 areas for low memory corruption
[    0.000000] init_memory_mapping: [mem 0x00000000-0x000fffff]
[    0.000000] init_memory_mapping: [mem 0x37400000-0x375fffff]
[    0.000000] init_memory_mapping: [mem 0x34000000-0x373fffff]
[    0.000000] init_memory_mapping: [mem 0x00100000-0x33ffffff]
[    0.000000] init_memory_mapping: [mem 0x37600000-0x377fdfff]
[    0.000000] ACPI: Early table checksum verification disabled
[    0.000000] ACPI: RSDP 0x000F0C90 000014 (v00 BOCHS )
[    0.000000] ACPI: RSDT 0x3FFE1A4A 000034 (v01 BOCHS  BXPCRSDT 00000001 BXPC 00000001)
[    0.000000] ACPI: FACP 0x3FFE1033 000074 (v01 BOCHS  BXPCFACP 00000001 BXPC 00000001)
[    0.000000] ACPI: DSDT 0x3FFE0040 000FF3 (v01 BOCHS  BXPCDSDT 00000001 BXPC 00000001)
[    0.000000] ACPI: FACS 0x3FFE0000 000040
[    0.000000] ACPI: SSDT 0x3FFE10A7 0008F3 (v01 BOCHS  BXPCSSDT 00000001 BXPC 00000001)
[    0.000000] ACPI: APIC 0x3FFE199A 000078 (v01 BOCHS  BXPCAPIC 00000001 BXPC 00000001)
[    0.000000] ACPI: HPET 0x3FFE1A12 000038 (v01 BOCHS  BXPCHPET 00000001 BXPC 00000001)
[    0.000000] 135MB HIGHMEM available.
[    0.000000] 887MB LOWMEM available.
[    0.000000]   mapped low ram: 0 - 377fe000
[    0.000000]   low ram: 0 - 377fe000
[    0.000000] Zone ranges:
[    0.000000]   DMA      [mem 0x00001000-0x00ffffff]
[    0.000000]   Normal   [mem 0x01000000-0x377fdfff]
[    0.000000]   HighMem  [mem 0x377fe000-0x3ffdffff]
[    0.000000] Movable zone start for each node
[    0.000000] Early memory node ranges
[    0.000000]   node   0: [mem 0x00001000-0x0009efff]
[    0.000000]   node   0: [mem 0x00100000-0x3ffdffff]
[    0.000000] Initmem setup node 0 [mem 0x00001000-0x3ffdffff]
[    0.000000] Using APIC driver default
[    0.000000] ACPI: PM-Timer IO Port: 0x608
[    0.000000] ACPI: LAPIC (acpi_id[0x00] lapic_id[0x00] enabled)
[    0.000000] ACPI: LAPIC_NMI (acpi_id[0xff] dfl dfl lint[0x1])
[    0.000000] ACPI: IOAPIC (id[0x00] address[0xfec00000] gsi_base[0])
[    0.000000] IOAPIC[0]: apic_id 0, version 17, address 0xfec00000, GSI 0-23
[    0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 dfl dfl)
[    0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 5 global_irq 5 high level)
[    0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 high level)
[    0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 10 global_irq 10 high level)
[    0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 11 global_irq 11 high level)
[    0.000000] Using ACPI (MADT) for SMP configuration information
[    0.000000] ACPI: HPET id: 0x8086a201 base: 0xfed00000
[    0.000000] smpboot: Allowing 1 CPUs, 0 hotplug CPUs
[    0.000000] e820: [mem 0x40000000-0xfffbffff] available for PCI devices
[    0.000000] setup_percpu: NR_CPUS:8 nr_cpumask_bits:8 nr_cpu_ids:1 nr_node_ids:1
[    0.000000] PERCPU: Embedded 13 pages/cpu @f6fea000 s32768 r0 d20480 u53248
[    0.000000] Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 260238
[    0.000000] Kernel command line: console=ttyS0 root=/dev/vda androidboot.hardware=qemu qemu=1 rootwait noinitrd init=/init androidboot.selinux=enforcing
[    0.000000] PID hash table entries: 4096 (order: 2, 16384 bytes)
[    0.000000] Dentry cache hash table entries: 131072 (order: 7, 524288 bytes)
[    0.000000] Inode-cache hash table entries: 65536 (order: 6, 262144 bytes)
[    0.000000] Initializing CPU#0
[    0.000000] Initializing HighMem for node 0 (000377fe:0003ffe0)
[    0.000000] Initializing Movable for node 0 (00000000:00000000)
[    0.000000] Memory: 1027068K/1048056K available (7663K kernel code, 550K rwdata, 2340K rodata, 588K init, 580K bss, 20988K reserved, 139144K highmem)
[    0.000000] virtual kernel memory layout:
[    0.000000]     fixmap  : 0xfff16000 - 0xfffff000   ( 932 kB)
[    0.000000]     pkmap   : 0xff800000 - 0xffa00000   (2048 kB)
[    0.000000]     vmalloc : 0xf7ffe000 - 0xff7fe000   ( 120 MB)
[    0.000000]     lowmem  : 0xc0000000 - 0xf77fe000   ( 887 MB)
[    0.000000]       .init : 0xc1a52000 - 0xc1ae5000   ( 588 kB)
[    0.000000]       .data : 0xc177c0d0 - 0xc1a50a80   (2898 kB)
[    0.000000]       .text : 0xc1000000 - 0xc177c0d0   (7664 kB)
[    0.000000] Checking if this processor honours the WP bit even in supervisor mode...Ok.
[    0.000000] SLUB: HWalign=32, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
[    0.000000] Hierarchical RCU implementation.
[    0.000000]  RCU restricting CPUs from NR_CPUS=8 to nr_cpu_ids=1.
[    0.000000] RCU: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=1
[    0.000000] NR_IRQS:2304 nr_irqs:256 0
[    0.000000] Console: colour *CGA 80x25
[    0.000000] console [ttyS0] enabled
[    0.000000] tsc: Fast TSC calibration using PIT
[    0.000000] tsc: Detected 2297.288 MHz processor
[    0.005264] Calibrating delay loop (skipped), value calculated using timer frequency.. 4594.57 BogoMIPS (lpj=2297288)
[    0.007083] pid_max: default: 32768 minimum: 301
[    0.007737] ACPI: Core revision 20140926
[    0.027123] ACPI: All ACPI Tables successfully acquired
[    0.030033] Security Framework initialized
[    0.031165] SELinux:  Initializing.
[    0.032658] Mount-cache hash table entries: 2048 (order: 1, 8192 bytes)
[    0.033073] Mountpoint-cache hash table entries: 2048 (order: 1, 8192 bytes)
[    0.044158] Initializing cgroup subsys freezer
[    0.046566] Last level iTLB entries: 4KB 0, 2MB 0, 4MB 0
[    0.046566] Last level dTLB entries: 4KB 0, 2MB 0, 4MB 0, 1GB 0
[    0.140138] Freeing SMP alternatives memory: 32K (c1ae5000 - c1aed000)
[    0.148491] Enabling APIC mode:  Flat.  Using 1 I/O APICs
[    0.152288] ..TIMER: vector=0x30 apic1=0 pin1=2 apic2=-1 pin2=-1
[    0.163090] smpboot: CPU0: Intel QEMU Virtual CPU version 2.2.0 (fam: 06, model: 06, stepping: 03)
[    0.165063] Performance Events: Broken PMU hardware detected, using software events only.
[    0.166000] Failed to access perfctr msr (MSR c1 is 0)
[    0.175662] x86: Booted up 1 node, 1 CPUs
[    0.176071] smpboot: Total of 1 processors activated (4594.57 BogoMIPS)
[    0.185807] devtmpfs: initialized
[    0.198634] RTC time: 13:30:44, date: 11/24/15
[    0.205720] kworker/u2:0 (15) used greatest stack depth: 7276 bytes left
[    0.207252] NET: Registered protocol family 16
[    0.214119] cpuidle: using governor ladder
[    0.214516] cpuidle: using governor menu
[    0.216196] ACPI: bus type PCI registered
[    0.218706] PCI: PCI BIOS revision 2.10 entry at 0xfd456, last bus=0
[    0.219033] PCI: Using configuration type 1 for base access
[    0.271241] kworker/u2:0 (46) used greatest stack depth: 7220 bytes left
[    0.274336] ACPI: Added _OSI(Module Device)
[    0.274642] ACPI: Added _OSI(Processor Device)
[    0.274931] ACPI: Added _OSI(3.0 _SCP Extensions)
[    0.275000] ACPI: Added _OSI(Processor Aggregator Device)
[    0.299149] ACPI: Interpreter enabled
[    0.299573] ACPI Exception: AE_NOT_FOUND, While evaluating Sleep State [\_S1_] (20140926/hwxface-580)
[    0.301070] ACPI Exception: AE_NOT_FOUND, While evaluating Sleep State [\_S2_] (20140926/hwxface-580)
[    0.302214] ACPI: (supports S0 S3 S5)
[    0.302495] ACPI: Using IOAPIC for interrupt routing
[    0.303653] PCI: Using host bridge windows from ACPI; if necessary, use "pci=nocrs" and report a bug
[    0.356480] ACPI: PCI Root Bridge [PCI0] (domain 0000 [bus 00-ff])
[    0.358000] acpi PNP0A03:00: _OSC: OS supports [ASPM ClockPM Segments MSI]
[    0.358000] acpi PNP0A03:00: _OSC failed (AE_NOT_FOUND); disabling ASPM
[    0.358000] acpi PNP0A03:00: fail to add MMCONFIG information, can't access extended PCI configuration space under this bridge.
[    0.358703] PCI host bridge to bus 0000:00
[    0.358974] pci_bus 0000:00: root bus resource [bus 00-ff]
[    0.359000] pci_bus 0000:00: root bus resource [io  0x0000-0x0cf7]
[    0.359000] pci_bus 0000:00: root bus resource [io  0x0d00-0xadff]
[    0.359000] pci_bus 0000:00: root bus resource [io  0xae0f-0xaeff]
[    0.359000] pci_bus 0000:00: root bus resource [io  0xaf20-0xafdf]
[    0.359000] pci_bus 0000:00: root bus resource [io  0xafe4-0xffff]
[    0.359000] pci_bus 0000:00: root bus resource [mem 0x000a0000-0x000bffff]
[    0.359000] pci_bus 0000:00: root bus resource [mem 0x40000000-0xfebfffff]
[    0.360285] kworker/u2:0 (95) used greatest stack depth: 7188 bytes left
[    0.372078] pci 0000:00:01.1: legacy IDE quirk: reg 0x10: [io  0x01f0-0x01f7]
[    0.373063] pci 0000:00:01.1: legacy IDE quirk: reg 0x14: [io  0x03f6]
[    0.374054] pci 0000:00:01.1: legacy IDE quirk: reg 0x18: [io  0x0170-0x0177]
[    0.375042] pci 0000:00:01.1: legacy IDE quirk: reg 0x1c: [io  0x0376]
[    0.378400] pci 0000:00:01.3: quirk: [io  0x0600-0x063f] claimed by PIIX4 ACPI
[    0.379076] pci 0000:00:01.3: quirk: [io  0x0700-0x070f] claimed by PIIX4 SMB
[    0.434543] ACPI: PCI Interrupt Link [LNKA] (IRQs 5 *10 11)
[    0.436964] ACPI: PCI Interrupt Link [LNKB] (IRQs 5 *10 11)
[    0.440210] ACPI: PCI Interrupt Link [LNKC] (IRQs 5 10 *11)
[    0.443534] ACPI: PCI Interrupt Link [LNKD] (IRQs 5 10 *11)
[    0.445618] ACPI: PCI Interrupt Link [LNKS] (IRQs *9)
[    0.447000] ACPI: Enabled 16 GPEs in block 00 to 0F
[    0.448000] vgaarb: loaded
[    0.449000] SCSI subsystem initialized
[    0.451690] ACPI: bus type USB registered
[    0.452484] usbcore: registered new interface driver usbfs
[    0.453298] usbcore: registered new interface driver hub
[    0.454693] usbcore: registered new device driver usb
[    0.456038] pps_core: LinuxPPS API ver. 1 registered
[    0.456184] pps_core: Software ver. 5.3.6 - Copyright 2005-2007 Rodolfo Giometti <giometti@linux.it>
[    0.456750] PTP clock support registered
[    0.458737] Advanced Linux Sound Architecture Driver Initialized.
[    0.459060] PCI: Using ACPI for IRQ routing
[    0.470120] NetLabel: Initializing
[    0.470368] NetLabel:  domain hash size = 128
[    0.470662] NetLabel:  protocols = UNLABELED CIPSOv4
[    0.471506] NetLabel:  unlabeled traffic allowed by default
[    0.472346] cfg80211: Calling CRDA to update world regulatory domain
[    0.474646] HPET: 3 timers in total, 0 timers will be used for per-cpu timer
[    0.475474] hpet0: at MMIO 0xfed00000, IRQs 2, 8, 0
[    0.476258] hpet0: 3 comparators, 64-bit 100.000000 MHz counter
[    0.480573] Switched to clocksource hpet
[    0.579729] pnp: PnP ACPI init
[    0.590946] pnp: PnP ACPI: found 6 devices
[    0.662848] NET: Registered protocol family 2
[    0.669740] TCP established hash table entries: 8192 (order: 3, 32768 bytes)
[    0.673664] TCP bind hash table entries: 8192 (order: 4, 65536 bytes)
[    0.676460] TCP: Hash tables configured (established 8192 bind 8192)
[    0.680268] TCP: reno registered
[    0.681667] UDP hash table entries: 512 (order: 2, 16384 bytes)
[    0.683401] UDP-Lite hash table entries: 512 (order: 2, 16384 bytes)
[    0.688826] NET: Registered protocol family 1
[    0.693656] RPC: Registered named UNIX socket transport module.
[    0.695520] RPC: Registered udp transport module.
[    0.696997] RPC: Registered tcp transport module.
[    0.698456] RPC: Registered tcp NFSv4.1 backchannel transport module.
[    0.701019] pci 0000:00:00.0: Limiting direct PCI/PCI transfers
[    0.702903] pci 0000:00:01.0: PIIX3: Enabling Passive Release
[    0.704571] pci 0000:00:01.0: Activating ISA DMA hang workarounds
[    0.715672] microcode: CPU0 sig=0x663, pf=0x1, revision=0x0
[    0.719265] microcode: Microcode Update Driver: v2.00 <tigran@aivazian.fsnet.co.uk>, Peter Oruba
[    0.724007] Scanning for low memory corruption every 60 seconds
[    0.732726] futex hash table entries: 256 (order: 2, 16384 bytes)
[    0.735653] audit: initializing netlink subsys (disabled)
[    0.738030] audit: type=2000 audit(1448371844.737:1): initialized
[    0.745488] HugeTLB registered 2 MB page size, pre-allocated 0 pages
[    0.762818] kworker/u2:0 (284) used greatest stack depth: 7132 bytes left
[    0.781558] VFS: Disk quotas dquot_6.5.2
[    0.784559] Dquot-cache hash table entries: 1024 (order 0, 4096 bytes)
[    0.797824] NFS: Registering the id_resolver key type
[    0.800738] Key type id_resolver registered
[    0.802599] Key type id_legacy registered
[    0.805468] msgmni has been set to 1734
[    0.815341] bounce: pool size: 64 pages
[    0.817598] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 251)
[    0.820866] io scheduler noop registered
[    0.822251] io scheduler deadline registered
[    0.824596] io scheduler cfq registered (default)
[    0.827991] pci_hotplug: PCI Hot Plug PCI Core version: 0.5
[    0.830255] input: Power Button as /devices/LNXSYSTM:00/LNXPWRBN:00/input/input0
[    0.830255] ACPI: Power Button [PWRF]
[    1.138002] ACPI: PCI Interrupt Link [LNKB] enabled at IRQ 10
[    1.428484] ACPI: PCI Interrupt Link [LNKC] enabled at IRQ 11
[    1.676846] ACPI: PCI Interrupt Link [LNKD] enabled at IRQ 11
[    1.679821] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
[    1.716440] serial 00:05: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
[    1.717722] tsc: Refined TSC clocksource calibration: 2297.311 MHz
[    1.725757] Non-volatile memory driver v1.3
[    1.726431] Linux agpgart interface v0.103
[    1.728885] [drm] Initialized drm 1.1.0 20060810
[    1.741642] loop: module loaded
[    1.762598]  vda: unknown partition table
[    1.772617]  vdb: unknown partition table
[    1.786982] scsi host0: ata_piix
[    1.789413] scsi host1: ata_piix
[    1.790514] ata1: PATA max MWDMA2 cmd 0x1f0 ctl 0x3f6 bmdma 0xc0a0 irq 14
[    1.790987] ata2: PATA max MWDMA2 cmd 0x170 ctl 0x376 bmdma 0xc0a8 irq 15
[    1.796440] e100: Intel(R) PRO/100 Network Driver, 3.5.24-k2-NAPI
[    1.796841] e100: Copyright(c) 1999-2006 Intel Corporation
[    1.798604] e1000: Intel(R) PRO/1000 Network Driver - version 7.3.21-k8-NAPI
[    1.799260] e1000: Copyright (c) 1999-2006 Intel Corporation.
[    1.799847] e1000e: Intel(R) PRO/1000 Network Driver - 2.3.2-k
[    1.800497] e1000e: Copyright(c) 1999 - 2014 Intel Corporation.
[    1.801660] sky2: driver version 1.30
[    1.804387] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
[    1.804862] ehci-pci: EHCI PCI platform driver
[    1.805968] ohci_hcd: USB 1.1 'Open' Host Controller (OHCI) Driver
[    1.806769] ohci-pci: OHCI PCI platform driver
[    1.807755] uhci_hcd: USB Universal Host Controller Interface driver
[    1.808715] usbcore: registered new interface driver usblp
[    1.809623] usbcore: registered new interface driver usb-storage
[    1.811084] i8042: PNP: PS/2 Controller [PNP0303:KBD,PNP0f13:MOU] at 0x60,0x64 irq 1,12
[    1.814434] serio: i8042 KBD port at 0x60,0x64 irq 1
[    1.814935] serio: i8042 AUX port at 0x60,0x64 irq 12
[    1.818016] mousedev: PS/2 mouse device common for all mice
[    1.821849] input: AT Translated Set 2 keyboard as /devices/platform/i8042/serio0/input/input1
[    1.824899] rtc_cmos 00:00: RTC can wake from S4
[    1.829566] rtc_cmos 00:00: rtc core: registered rtc_cmos as rtc0
[    1.831068] rtc_cmos 00:00: alarms up to one day, 114 bytes nvram, hpet irqs
[    1.834502] device-mapper: ioctl: 4.28.0-ioctl (2014-09-17) initialised: dm-devel@redhat.com
[    1.835796] hidraw: raw HID events driver (C) Jiri Kosina
[    1.840713] usbcore: registered new interface driver usbhid
[    1.841325] usbhid: USB HID core driver
[    1.843296] ashmem: initialized
[    1.854023] Netfilter messages via NETLINK v0.30.
[    1.855663] nf_conntrack version 0.5.0 (16048 buckets, 64192 max)
[    1.859317] ctnetlink v0.93: registering with nfnetlink.
[    1.863908] ip_tables: (C) 2000-2006 Netfilter Core Team
[    1.867329] TCP: cubic registered
[    1.867600] Initializing XFRM netlink socket
[    1.870879] NET: Registered protocol family 10
[    1.878957] ip6_tables: (C) 2000-2006 Netfilter Core Team
[    1.881737] sit: IPv6 over IPv4 tunneling driver
[    1.885818] NET: Registered protocol family 17
[    1.887502] 9pnet: Installing 9P2000 support
[    1.888603] Key type dns_resolver registered
[    1.888982] mce: Unable to init device /dev/mcelog (rc: -5)
[    1.890751] Using IPI No-Shortcut mode
[    1.893559] registered taskstats version 1
[    1.898841]   Magic number: 7:690:534
[    1.899820] console [netcon0] enabled
[    1.900334] netconsole: network logging started
[    1.902459] ALSA device list:
[    1.902707]   No soundcards found.
[    1.909900] kworker/u2:0 (822) used greatest stack depth: 7060 bytes left
[    1.951710] ata2.00: ATAPI: QEMU DVD-ROM, 2.2.0, max UDMA/100
[    1.953775] ata2.00: configured for MWDMA2
[    1.963257] scsi 1:0:0:0: CD-ROM            QEMU     QEMU DVD-ROM     2.2. PQ: 0 ANSI: 5
[    1.979583] sr 1:0:0:0: [sr0] scsi3-mmc drive: 4x/4x cd/rw xa/form2 tray
[    1.980352] cdrom: Uniform CD-ROM driver Revision: 3.20
[    1.984871] sr 1:0:0:0: Attached scsi generic sg0 type 5
[    2.429521] input: ImExPS/2 Generic Explorer Mouse as /devices/platform/i8042/serio1/input/input3
[    2.431346] md: Waiting for all devices to be available before autodetect
[    2.432217] md: If you don't use raid, use raid=noautodetect
[    2.434205] md: Autodetecting RAID arrays.
[    2.434205] md: Scanned 0 and added 0 devices.
[    2.434205] md: autorun ...
[    2.434205] md: ... autorun DONE.
[    2.439351] EXT4-fs (vda): couldn't mount as ext3 due to feature incompatibilities
[    2.441356] EXT4-fs (vda): couldn't mount as ext2 due to feature incompatibilities
[    2.458722] EXT4-fs (vda): mounted filesystem with ordered data mode. Opts: (null)
[    2.459580] VFS: Mounted root (ext4 filesystem) readonly on device 253:0.
[    2.462292] devtmpfs: mounted
[    2.496824] Freeing unused kernel memory: 588K (c1a52000 - c1ae5000)
[    2.498431] Write protecting the kernel text: 7668k
[    2.499340] Write protecting the kernel read-only data: 2344k
[    2.595755] init: init first stage started!
[    2.658461] audit: type=1403 audit(1448371846.657:2): policy loaded auid=4294967295 ses=4294967295
[    2.668560] audit: type=1404 audit(1448371846.668:3): enforcing=1 old_enforcing=0 auid=4294967295 ses=4294967295
[    2.671516] init: (Initializing SELinux enforcing took 0.07s.)
[    2.711282] init: init second stage started!
[    2.722767] Switched to clocksource tsc
[    2.737542] init: Running restorecon...
[    2.792615] init: waitpid failed: No child processes
[    2.795002] init: (Loading properties from /default.prop took 0.00s.)
[    2.805479] init: property 'ro.zygote' doesn't exist while expanding '/init.${ro.zygote}.rc'
[    2.806433] init: /init.rc: 10: error while expanding import
[    2.819560] init: /init.environ.rc: 10: export requires 2 arguments
[    2.820265] init: /init.environ.rc: 11: export requires 2 arguments
[    2.821256] init: (Parsing /init.environ.rc took 0.00s.)
[    2.824274] init: (Parsing /init.usb.rc took 0.00s.)
[    2.826419] init: (Parsing /init.qemu.rc took 0.00s.)
[    2.826882] init: (Parsing /init.rc took 0.03s.)
[    2.835543] init: Starting service 'ueventd'...
[    2.839990] init: Waiting for /dev/.coldboot_done...
[    2.852393] ueventd: ueventd started!
[    3.330544] ueventd: Coldboot took 0.46s.
[    3.340376] init: Waiting for /dev/.coldboot_done took 0.50s.
[    3.341391] init: /dev/hw_random not found
[    3.375915] init: write_file: Unable to open '/proc/sys/kernel/hung_task_timeout_secs': No such file or directory
[    3.376868] init: write_file: Unable to open '/proc/cpu/alignment': No such file or directory
[    3.377873] init: write_file: Unable to open '/proc/sys/kernel/sched_latency_ns': No such file or directory
[    3.378822] init: write_file: Unable to open '/proc/sys/kernel/sched_wakeup_granularity_ns': No such file or directory
[    3.379867] init: write_file: Unable to open '/proc/sys/kernel/sched_compat_yield': No such file or directory
[    3.387761] init: write_file: Unable to write to '/dev/cpuctl/cpu.shares': Invalid argument
[    3.388652] init: write_file: Unable to open '/dev/cpuctl/cpu.rt_runtime_us': Permission denied
[    3.389535] init: write_file: Unable to open '/dev/cpuctl/cpu.rt_period_us': Permission denied
[    3.391996] init: write_file: Unable to open '/dev/cpuctl/bg_non_interactive/cpu.rt_runtime_us': Permission denied
[    3.393003] init: write_file: Unable to open '/dev/cpuctl/bg_non_interactive/cpu.rt_period_us': Permission denied
[    3.401957] init: write_file: Unable to open '/proc/sys/abi/swp': No such file or directory
[    3.403205] init: /dev/hw_random not found
[    3.412836] EXT4-fs (vdb): Ignoring removed nomblk_io_submit option
[    3.423081] EXT4-fs (vdb): mounted filesystem with ordered data mode. Opts: errors=remount-ro,nomblk_io_submit
[    3.424361] fs_mgr: check_fs(): mount(/dev/block/vdb,/data,ext4)=0: Success
[    3.436895] fs_mgr: check_fs(): unmount(/data) succeeded
[    3.439527] fs_mgr: Not running /system/bin/e2fsck on /dev/block/vdb (executable not in system image)
[    3.441267] EXT4-fs (vdb): Ignoring removed nomblk_io_submit option
[    3.447772] EXT4-fs (vdb): mounted filesystem with ordered data mode. Opts: nomblk_io_submit,errors=panic
[    3.448820] fs_mgr: __mount(source=/dev/block/vdb,target=/data,type=ext4)=0
[    3.451827] init (1168) used greatest stack depth: 6468 bytes left
[    3.459730] init: (Parsing /system/etc/init/apmanager.rc took 0.00s.)
[    3.461522] init: (Parsing /system/etc/init/avahi-daemon.rc took 0.00s.)
[    3.462869] init: (Parsing /system/etc/init/bluetoothtbd.rc took 0.00s.)
[    3.464715] init: (Parsing /system/etc/init/brillo.rc took 0.00s.)
[    3.466550] init: (Parsing /system/etc/init/crash_reporter.rc took 0.00s.)
[    3.467863] init: (Parsing /system/etc/init/firewalld.rc took 0.00s.)
[    3.469401] init: (Parsing /system/etc/init/keystore.rc took 0.00s.)
[    3.470621] init: (Parsing /system/etc/init/logcatd.rc took 0.00s.)
[    3.472005] init: (Parsing /system/etc/init/logd.rc took 0.00s.)
[    3.473511] init: (Parsing /system/etc/init/mediaserver.rc took 0.00s.)
[    3.474763] init: (Parsing /system/etc/init/metrics_daemon.rc took 0.00s.)
[    3.476417] init: (Parsing /system/etc/init/nativepowerman.rc took 0.00s.)
[    3.477567] init: (Parsing /system/etc/init/perfprofd.rc took 0.00s.)
[    3.478756] init: (Parsing /system/etc/init/sensorservice.rc took 0.00s.)
[    3.480315] init: (Parsing /system/etc/init/servicemanager.rc took 0.00s.)
[    3.481569] init: (Parsing /system/etc/init/shill.rc took 0.00s.)
[    3.482765] init: (Parsing /system/etc/init/tlsdated.rc took 0.00s.)
[    3.483928] init: (Parsing /system/etc/init/update_engine.rc took 0.00s.)
[    3.485368] init: (Parsing /system/etc/init/weaved.rc took 0.00s.)
[    3.486635] init: (Parsing /system/etc/init/webservd.rc took 0.00s.)
[    3.494926] init: Starting service 'logd'...
[    3.497878] EXT4-fs (vda): re-mounted. Opts: (null)
[    3.518603] init: do_start: Service vold not found
[    3.544280] init: Not bootcharting.
[    3.588744] random: logd urandom read with 10 bits of entropy available
[    3.738645] init: cannot find '/system/bin/tzdatacheck' (No such file or directory), disabling 'exec 1 (/system/bin/tzdatacheck)'
[    3.759213] init: (Loading properties from /system/build.prop took 0.00s.)
[    3.759798] init: (Loading properties from /vendor/build.prop took 0.00s.)
[    3.760603] init: (Loading properties from /factory/factory.prop took 0.00s.)
[    3.761525] init: (Loading properties from /data/local.prop took 0.00s.)
[    3.762787] fs_mgr: Cannot open file /fstab.qemu
[    3.764467] init: unable to read fstab /fstab.qemu: No such file or directory
[    3.765754] init: Starting service 'logd-reinit'...
[    3.804286] init: cannot find '/sbin/healthd' (No such file or directory), disabling 'healthd'
[    3.808783] init: Starting service 'wifi-setup'...
[    3.814465] init: Starting service 'dbus'...
[    3.824271] init: Starting service 'servicemanager'...
[    3.844729] init: Starting service 'initnetwork'...
[    3.862574] init: Starting service 'firewall-setup'...
[    3.873907] init: Starting service 'console'...
[    3.890840] init: Starting service 'adbd'...
[    3.912691] init: cannot find '/system/bin/install-recovery.sh' (No such file or directory), disabling 'flash_recovery'
[    3.945878] init: Starting service 'avahi-daemon'...
[    3.958817] init: Starting service 'bluetoothtbd'...
[    3.996929] init: Starting service 'wpa_supplicant'...
[    4.039000] init: Starting service 'keystore'...
[    4.084590] init: Starting service 'media'...
[    4.120796] init: Starting service 'nativepowerman'...
[    4.153992] init: Starting service 'sensorservice'...
[    4.224625] init: Starting service 'crash_reporter'...
[    4.279586] init: Starting service 'crash_sender'...
[    4.335429] init: Starting service 'metrics_daemon'...
[    4.378867] init: Starting service 'perfprofd'...
[    4.435754] init: Starting service 'shill'...
[    4.502127] init: Starting service 'tlsdated'...
[    4.566273] init: Starting service 'update_engine'...
[    4.638470] init: Starting service 'weaved'...
[    4.709987] init: Starting service 'webservd'...
[    4.843590] init: Service 'logd-reinit' (pid 1177) exited with status 145
[    5.047490] init: write_file: Unable to open '/sys/class/android_usb/android0/enable': No such file or directory
[    5.160479] init: write_file: Unable to open '/sys/class/android_usb/android0/idVendor': No such file or directory
[    5.254434] init: write_file: Unable to open '/sys/class/android_usb/android0/idProduct': No such file or directory
[    5.331494] init: write_file: Unable to open '/sys/class/android_usb/android0/functions': No such file or directory
[    5.435431] init: write_file: Unable to open '/sys/class/android_usb/android0/enable': No such file or directory
[    7.270465] init: Service 'crash_reporter' (pid 1192) exited with status 0
[    7.605414] iptables (1203) used greatest stack depth: 6268 bytes left
[    7.759352] audit: type=1400 audit(1448371851.757:4): avc:  denied  { sys_module } for  pid=1204 comm="ifconfig" capability=16  scontext=u:r:brillo_setup:s0 tcontext=u:r:brillo_setup:s0 tclass=capability permissive=0
[    9.131357] init: Starting service 'apmanager'...
[    9.284642] init.wifi-setup (1178) used greatest stack depth: 6240 bytes left
[    9.285892] init: Service 'wifi-setup' (pid 1178) exited with status 0
[   11.457417] audit: type=1400 audit(1448371853.965:5): avc:  denied  { dac_override } for  pid=1181 comm="initnetwork.sh" capability=1  scontext=u:r:brillo_setup:s0 tcontext=u:r:brillo_setup:s0 tclass=capability permissive=0
[   11.665465] init: Service 'initnetwork' (pid 1181) exited with status 126
[   13.158430] logd.auditd: start
[   13.361299] logd.klogd: 13158841665
[   13.697620] capability: warning: `wpa_supplicant' uses 32-bit capabilities (legacy support in use)
[   14.055736] tlsdate-helper (1231) used greatest stack depth: 6092 bytes left
[   21.170392] init: Starting service 'firewalld'...
[   21.192285] init: Service 'firewall-setup' (pid 1182) exited with status 0

底下是我在這個模擬器的Terminal裏面下的一些指令過程

$ su
# ls
acct         etc               init.usb.rc       sbin             sys
cache        file_contexts.bin lost+found        sdcard           system
config       fstab.device      mnt               seapp_contexts   ueventd.rc
d            init              oem               selinux_version
data         init.environ.rc   proc              sepolicy
default.prop init.qemu.rc      property_contexts service_contexts
dev          init.rc           root              storage
# df -h
Filesystem     Size  Used Avail Use% Mounted on
/dev/root      726M   96M  630M  14% /
tmpfs          502M   20K  502M   1% /dev
none           502M   12K  502M   1% /sys/fs/cgroup
tmpfs          502M     0  502M   0% /mnt
/dev/block/vdb 533M   31M  502M   6% /data
tmpfs          502M     0  502M   0% /storage
# free -m
                total        used        free      shared     buffers
Mem:             1003          76         927           0           1
-/+ buffers/cache:             75         928
Swap:               0           0           0
# ps
USER      PID   PPID  VSIZE  RSS   WCHAN            PC  NAME
root      1     0     3304   1560     ep_poll 08134545 S /init
root      2     0     0      0       kthreadd 00000000 S kthreadd
root      3     2     0      0     smpboot_th 00000000 S ksoftirqd/0
root      4     2     0      0     worker_thr 00000000 S kworker/0:0
root      5     2     0      0     worker_thr 00000000 S kworker/0:0H
root      6     2     0      0     worker_thr 00000000 S kworker/u2:0
root      7     2     0      0     rcu_gp_kth 00000000 S rcu_sched
root      8     2     0      0     rcu_gp_kth 00000000 S rcu_bh
root      9     2     0      0     smpboot_th 00000000 S migration/0
root      10    2     0      0     rescuer_th 00000000 S khelper
root      11    2     0      0      devtmpfsd 00000000 S kdevtmpfs
root      12    2     0      0     rescuer_th 00000000 S netns
root      13    2     0      0     worker_thr 00000000 S kworker/u2:1
root      14    2     0      0     rescuer_th 00000000 S perf
root      45    2     0      0     rescuer_th 00000000 S writeback
root      47    2     0      0     rescuer_th 00000000 S crypto
root      49    2     0      0     rescuer_th 00000000 S bioset
root      50    2     0      0     rescuer_th 00000000 S kblockd
root      134   2     0      0     rescuer_th 00000000 S ata_sff
root      138   2     0      0     rescuer_th 00000000 S md
root      145   2     0      0     worker_thr 00000000 S kworker/0:1
root      146   2     0      0     rescuer_th 00000000 S cfg80211
root      250   2     0      0     rescuer_th 00000000 S rpciod
root      275   2     0      0         kswapd 00000000 S kswapd0
root      293   2     0      0     fsnotify_m 00000000 S fsnotify_mark
root      302   2     0      0     rescuer_th 00000000 S nfsiod
root      337   2     0      0     rescuer_th 00000000 S acpi_thermal_pm
root      339   2     0      0     worker_thr 00000000 S kworker/u2:2
root      753   2     0      0     scsi_error 00000000 S scsi_eh_0
root      755   2     0      0     rescuer_th 00000000 S scsi_tmf_0
root      757   2     0      0     scsi_error 00000000 S scsi_eh_1
root      759   2     0      0     rescuer_th 00000000 S scsi_tmf_1
root      761   2     0      0     worker_thr 00000000 S kworker/u2:3
root      771   2     0      0     rescuer_th 00000000 S kpsmoused
root      780   2     0      0     rescuer_th 00000000 S binder
root      786   2     0      0     worker_thr 00000000 S kworker/0:2
root      798   2     0      0     rescuer_th 00000000 S ipv6_addrconf
root      810   2     0      0     rescuer_th 00000000 S deferwq
root      812   2     0      0     worker_thr 00000000 S kworker/u2:4
root      887   2     0      0     worker_thr 00000000 S kworker/0:3
root      898   2     0      0     kjournald2 00000000 S jbd2/vda-8
root      899   2     0      0     rescuer_th 00000000 S ext4-rsv-conver
root      902   1     3372   1476  poll_sched 08134650 S /sbin/ueventd
root      1172  2     0      0     worker_thr 00000000 S kworker/0:1H
root      1173  2     0      0     kjournald2 00000000 S jbd2/vdb-8
root      1174  2     0      0     rescuer_th 00000000 S ext4-rsv-conver
logd      1175  1     11332  2608  sigsuspend b7619ef1 S /system/bin/logd
dbus      1179  1     5676   2984  poll_sched b7538cd0 S /system/bin/dbus-daemon
system    1180  1     4604   2092  binder_thr b749dbd6 S /system/bin/servicemanager
shell     1183  1     4452   2280  sigsuspend b760bef1 S /system/bin/sh
root      1184  1     3640   692   poll_sched 0810f250 S /sbin/adbd
system    1185  1     5324   2552  poll_sched b7543cd0 S avahi-daemon: running [linux.local]
bluetooth 1186  1     38728  8756  futex_wait b73a48b2 S /system/bin/bluetoothtbd
system    1187  1     30356  9992  poll_sched b70cfd55 S /system/bin/wpa_supplicant
keystore  1188  1     28860  8636  binder_thr b7380bd6 S /system/bin/keystore
media     1189  1     71472  15108 binder_thr b65edbd6 S /system/bin/mediaserver
system    1190  1     28488  8728     ep_poll b5ccb9d5 S /system/bin/nativepowerman
root      1191  1     30168  8732  binder_thr b5dc5bd6 S /system/bin/sensorservice
root      1193  1     4452   2248  poll_sched b753ad55 S /system/bin/sh
system    1194  1     33164  12312    ep_poll b6fe49d5 S /system/bin/metrics_daemon
root      1195  1     4688   2096  hrtimer_na b7642e91 S /system/xbin/perfprofd
root      1196  1     10684  7308     ep_poll b722b9d5 S /system/bin/shill
tlsdate   1197  1     6200   3272     ep_poll b73959d5 S /system/bin/tlsdated
root      1198  1     11412  7352     ep_poll b6cb89d5 S /system/bin/update_engine
system    1200  1     34092  13348    ep_poll b6b209d5 S /system/bin/weaved
system    1201  1     32944  12784    ep_poll b586a9d5 S /system/bin/webservd
root      1206  1197  6200   356    pipe_wait b7397096 S /system/bin/tlsdated
system    1212  1     8720   5828     ep_poll b71479d5 S /system/bin/apmanager
root      1221  2     0      0     kauditd_th 00000000 S kauditd
system    1255  1     7524   5356     ep_poll b732c9d5 S /system/bin/firewalld
root      1267  1183  4452   2332  sigsuspend b75dbef1 S /system/bin/sh
root      1273  1267  4660   2184           0 b74e6096 R ps
# ifconfig -a
sit0      Link encap:IPv6-in-IPv4
          NOARP  MTU:1480  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:0 TX bytes:0

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope: Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:64 errors:0 dropped:0 overruns:0 frame:0
          TX packets:64 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:4480 TX bytes:4480
$ reboot -p
[ 1363.786815] SysRq : Emergency Remount R/O
[ 1363.797520] EXT4-fs (vdb): re-mounted. Opts: (null)
[ 1363.802681] Emergency Remount complete
[ 1364.902612] ACPI: Preparing to enter system sleep state S5
[ 1364.905890] reboot: Power down

過程中遇到過的問題
編譯Java相關程式必需使用1.7x版本以上, 否則會出現下面的訊息

Checking build tools versions...
************************************************************
You are attempting to build with the incorrect version
of java.

Your version is: java version "1.6.0_45" Java(TM) SE Runtime Environment (build 1.6.0_45-b06) Java HotSpot(TM) 64-Bit Server VM (build 20.45-b01, mixed mode).
The required version is: "1.7.x"

Please follow the machine setup instructions at
    https://source.android.com/source/initializing.html
************************************************************
build/core/main.mk:203: *** stop.
make: *** [out/build-brilloemulator_x86_64.ninja] Error 1

解決方法:

sudo apt-get install openjdk-7-jdk icedtea-7-plugin
sudo update-java-alternatives -s java-1.7.0-openjdk-amd64

底下有一份Dipak Shelke Patil的PowerPoint可以參考^^

Brillo operating system(os) from dipakshelkepatil

可以看一下這個地方https://android.googlesource.com/brillo/manifest/

目前有的branch有底下幾個
(1)master
(2)brillo-m7-dev
(3)brillo-m7-mr-dev
(4)brillo-m7-release