m、mm、mmm命令差异

android源码目录下的build/envsetup.sh文件开头可以看到如下描述：

function help() {
cat <<EOF
Invoke ". build/envsetup.sh" from your shell to add the following functions to your environment:
- croot:   Changes directory to the top of the tree.
- m:       Makes from the top of the tree.
- mm:      Builds all of the modules in the current directory.
- mmm:     Builds all of the modules in the supplied directories.
- cgrep:   Greps on all local C/C++ files.
- jgrep:   Greps on all local Java files.
- resgrep: Greps on all local res/*.xml files.
- godir:   Go to the directory containing a file.

Look at the source to view more functions. The complete list is:
EOF
    T=$(gettop)
    local A
    A=""
    for i in `cat $T/build/envsetup.sh | sed -n "/^function /s/function \([a-z_]*\).*/\1/p" | sort`; do
      A="$A $i"
    done
    echo $A
}

设置环境，在src目录执行如下命令：

. build/envsetup.sh

对平台的配置：

lunch

再选择对应平台

编译所有的模块:

m

编译当前目录下的模块，当前目录下要有Android.mk文件:

mm

编译指定路径下的模块，指定路径下要有Android.mk文件:

mmm

eg:当前目录为源码根目录，编译\hardware\libhardware_legacy\power模块: 
. build/envsetup.sh 
mmm -B hardware/libhardware_legacy/power/     //-B全新编译

或者 ： 
. build/envsetup.sh 
cd hardware/libhardware_legacy/power/ 
mm