itoa()

char* itoa(int val, int base){
 
     static char buf[32] = {0};
 
     int i = 30;
 
     for(; val && i ; --i, val /= base)
 
          buf[i] = "0123456789abcdef"[val % base];
 
     return &buf[i+1];
 
}

Powerd by: http://tohtml.com/

make 命令 & makefile

makefile syntax

• dependencies (相依性項目)
• one target (目標項目)
• some source code files
• (target), (semicolon), (space or tab), ....., (source code files), (space or tab), .....
• e.g. all: myapp myapp.l

• rules (法則)
• the rules illustrate how to generate a target
• (tab)
• the rules muse be on the same line

• comment (註解)
• (#)

• macro (巨集)
• define the macro => MACRONAME = value
• access the macro => $(MACRONAME), ${MACRONAME}

• -
• make will ignore the error
• e.g. -mkdir
• e.g. -rm -r

• @
• make will not output the executed command on standard output

• #這是makefile的格式(註解) 
  [target]: [dependency] [dependency] 
  [TAB][rule] 
  [TAB][rule] 
  [target]: [dependency] 
  [TAB][rule] 

make options

-k : 會讓make再遇到錯誤之時，仍然繼續執行而不會停在第一個問題點。可以利用這個選項找出發生問題的原始碼檔案。

-n : 告訴make只列出要進行的工作，而不會真正去執行它。

-f : tell the make to use the as a makefile. Otherwise, the make will use the makefile, Makefile (recommend).

-p : 要求 make 印出內建法則

-j3 : use the 3 cores 

Automatic Varaiables

$@ :  The name of the current target 

$% :  The filename element of an archive member specification

$<: first="" he="" name="" nbsp="" of="" p="" prerequisite="" the="">
$?:    The names of all prerequisites that are newer than the target, separated by spaces,代表須要重建(被修改)的相依性項目

$^:     The names of all prerequisites, separated by spaces. This is list has duplicated names removed.

$+:     Similar to $^, except $+ includes duplicateds.. This variable was created for specific situations such as arguments to linkers where duplicated values have meaning.

$*:    The stem of the target filename. A stem is typically a filename without its suffix. Current dependencies without the extension (副檔名)

1. define the marcro : 1) make CC=c89    2) make "CC = c89"
2. Use the all as the first target in makefile
3. all (target)
4. install (target)
5. uninstall (target)
6. clean (target)

GNU gcc

gcc -MM : generate a dependency list to make

Conventional Macros (common built in rules of makefiles)

typing "make −p" to print out the defaults

AR	Archive−maintaining program; default is `ar'.
AS	Program for compiling assembly files; default is `as'.
CC	Program for compiling C programs; default is `cc'.
CO	Program for checking out files from RCS; default is `co'.
CXX	Program for compiling C++ programs; default is `g++'.
CPP	Program for running the C preprocessor, with results to standard output; default is `$(CC) -E'.

ARFLAGS	Flags to give the archive-maintaining program; default is `rv'.
ASFLAGS	Extra flags to give to the assembler when explicitly invoked on a `.s' or `.S' file.
CFLAGS	Extra flags to give to the C compiler.
CXXFLAGS	Extra flags to give to the C compiler.
COFLAGS	Extra flags to give to the RCS co program.
CPPFLAGS	Extra flags to give to the C preprocessor and programs, which use it (such as C and Fortran compilers).

Conditional Directives

• ifeq
• ifneq
• ifdef
• ifndef
• else
• endif

e.g.

ifeq (arg1, arg2)
ifeq 'arg1' 'arg2'
ifeq "arg1" "arg2"
ifeq "arg1" 'arg2'
ifeq 'arg1' "arg2" 

相關文件

• Linux 程式設計教學手冊 CH9
• 撰寫Makefile教學
• http://hsian-studio.blogspot.tw/2008/09/makefile_08.html
• Makefile語法簡介
• http://tetralet.luna.com.tw/index.php?op=ViewArticle&articleId=185&blogId=1
• 利用Autotools來建立Makefile檔案
• http://tetralet.luna.com.tw/index.php?op=ViewArticle&articleId=200&blogId=1
• 實戰Makefile.am
• http://xubiechusheng.blog.sohu.com/68789033.html
• TutorialPoint Quick Guide
• http://www.tutorialspoint.com/makefile/makefile_quick_guide.htm
• Autotools Tutorial for Beginners
• http://markuskimius.wikidot.com/programming:tut:autotools/

Linux 壓縮與解壓縮

.tar
解壓：tar xvf FileName.tar
壓缩：tar cvf FileName.tar DirName
（注：tar是包裹(把多個檔案合成一個)，不是壓缩！）
---------------------------------------------
.gz
解壓1：gunzip FileName.gz
解壓2：gzip -d FileName.gz
壓缩：gzip FileName
.tar.gz
解壓：tar zxvf FileName.tar.gz
壓缩：tar zcvf FileName.tar.gz DirName
---------------------------------------------
.bz2
解壓1：bzip2 -d FileName.bz2
解壓2：bunzip2 FileName.bz2
壓缩： bzip2 -z FileName
.tar.bz2
解壓：tar jxvf FileName.tar.bz2
壓缩：tar jcvf FileName.tar.bz2 DirName
---------------------------------------------
.bz
解壓1：bzip2 -d FileName.bz
解壓2：bunzip2 FileName.bz
壓缩：未知
.tar.bz
解壓：tar jxvf FileName.tar.bz
壓缩：未知
---------------------------------------------
.Z
解壓：uncompress FileName.Z
壓缩：compress FileName
.tar.Z
解壓：tar Zxvf FileName.tar.Z
壓缩：tar Zcvf FileName.tar.Z DirName
---------------------------------------------
.tgz
解壓：tar zxvf FileName.tgz
壓缩：未知
.tar.tgz
解壓：tar zxvf FileName.tar.tgz
壓缩：tar zcvf FileName.tar.tgz FileName
---------------------------------------------
.zip
解壓：unzip FileName.zip
壓缩：zip FileName.zip DirName
---------------------------------------------
.rar
解壓：rar a FileName.rar
壓缩：rar e FileName.rar


rar請到：http://www.rarsoft.com/download.htm 下載！
解壓後請将rar_static拷貝到/usr/bin目錄（其他由$PATH環境變數指定的目錄也可以）：
[root@www2 tmp]# cp rar_static /usr/bin/rar
---------------------------------------------
.lha
解壓：lha -e FileName.lha
壓缩：lha -a FileName.lha FileName

lha請到：http://www.infor.kanazawa-it.ac.jp/~ishii/lhaunix/下載！
解壓後請将lha拷贝到/usr/bin目錄（其他由$PATH環境變數指定的目錄也可以）：
[root@www2 tmp]# cp lha /usr/bin/
---------------------------------------------
.tar .tgz .tar.gz .tar.Z .tar.bz .tar.bz2 .zip .cpio .rpm .deb .slp .arj .rar .ace .lha .lzh .lzx .lzs .arc .sda .sfx .lnx .zoo .cab .kar .cpt .pit .sit .sea
解壓：sEx x FileName.*
壓缩：sEx a FileName.* FileName

sEx只是調用相關程序，本身並無壓缩、解壓功能，請注意！\r
sEx請到：http://sourceforge.net/projects/sex下載！
解壓后請将sEx拷贝到/usr/bin目錄（其他由$PATH環境變數指定的目錄也可以）：
[root@www2 tmp]# cp sEx /usr/bin/ 

Remove sun-java6-jdk on UBUNTU

SDK instal and path set up  

http://wallyjue.blogspot.com/2011/04/ubuntu-1004java-jdk-15.html

Remove java
$sudo apt-get remove sun-java6-jdk
$sudo apt-get remove sun-java6-jre
$sudo apt-get remove sun-java6-bin

Introduce the Linux Directories

If you look at the Linux file hierarchy, you find the following :

• /bin - common binaries
• /sbin - Binaries used for system administration are placed here.
• /boot - static files of the boot loader. Usually it contain the Linux kernel, Grub boot loader files and so on.
• /dev - device files such as your CD drive, hard disk, and any other physical device. (In Linux/Unix, the common premise is that everything is a file).
• /home - user home directories are found here. In unices like FreeBSD, the home directoriesare found in /usr/home. And in Solaris it is in /export. So quite a big difference here.
• /lib - Essential shared libraries and kernel modules
• /mnt - temporary mount point useful for when you insert your USB stick and it gets mounted under /mnt. Though in Ubuntu and the likes, it is usually mounted under /media.
• /var - variable data, such as logs, news, mail spool files and so on which is constantly being modified by various programs running on your system.
• /tmp - temporary files are placed here by default.
• /usr - the secondary hierarchy which contain its own bin and sbin sub-directories.
• /etc - Usually contain the configuration files for all the programs that run on your Linux/Unix system.
• /opt - Third party application packages which does not conform to the standard Linux file hierarchy can be installed here.
• /srv - Contains data for services provided by the system.

Problem: xxx is not in the sudoers file

sudo时提示"xxx is not in the sudoers file. This incident will be reported.其中XXX是你的用户名，也就是你的用户名没有权限使用sudo,我们只要修改一下/etc/sudoers文件就行了。下面是修改方法：

1）进入超级用户模式。也就是输入"su -",系统会让你输入超级用户密码，输入密码后就进入了超级用户模式。（当然，你也可以直接用root用） 

2）添加文件的写权限。也就是输入命令"chmod u+w /etc/sudoers"。

 
3）编辑/etc/sudoers文件。也就是输入命令"sudo gedit  /etc/sudoers",输入"i"进入编辑模式，找到这一 行："root ALL=(ALL) ALL"在起下面添加"xxx ALL=(ALL) ALL"(这里的xxx是你的用户名)，然后保存（就是先按一 下Esc键，然后输入":wq"）退出。 

4）撤销文件的写权限。也就是输入命令"chmod u-w /etc/sudoers"。

Install repo

Problem:
-----------------------------------------------------------------------------------------------------------------------------
fatal: unable to connect a socket


Resolution:
-----------------------------------------------------------------------------------------------------------------------------
會出現這個問題是因為Android git   Server的DNS查詢回應太慢的關係可依照下列方法解決
1.  ping android.git.kernel.org ,將結果的IP記錄下來
2.  更改系統的hosts, 將android.git.kernel.org與IP之對照表建立起來
     方法：sudo gedit /etc/hosts 新增一行 IP address 對照到 android.git.kernel.org
3. 修改專案目錄下的  .repo/manifest.xml, 將android.git.kernel.org 替換成剛剛找到的IP
4. repo init ................................................................................


-----------------------------------------------------------------------------------------------------------------------------


http://5i01.com/topicdetail.php?f=423&t=1130384&p=1