private static ZygoteConnection acceptCommandPeer(String abiList) {
try {
return new ZygoteConnection(sServerSocket.accept(), abiList);
} catch (IOException ex) {
throw new RuntimeException(
“IOException during accept()”, ex);
}
}

然后调用runOnce()方法读取连接请求里的数据，然后创建新进程。

此外，连接的过程中服务端接受的到客户端的connect()操作会执行accpet()操作，建立连接手，客户端通过write()写数据，服务端通过read()读数据。

1.3 ZygoteConnection.runOnce()

class ZygoteConnection {

boolean runOnce() throws ZygoteInit.MethodAndArgsCaller {

String args[];
Arguments parsedArgs = null;
FileDescriptor[] descriptors;

try {
//读取客户端发过来的参数列表
args = readArgumentList();
descriptors = mSocket.getAncillaryFileDescriptors();
} catch (IOException ex) {
Log.w(TAG, "IOException on command socket " + ex.getMessage());
closeSocket();
return true;
}

//… 参数处理

try {

//… 参数处理

//调用Zygote.forkAndSpecialize（来fork出新进程
pid = Zygote.forkAndSpecialize(parsedArgs.uid, parsedArgs.gid, parsedArgs.gids,
parsedArgs.debugFlags, rlimits, parsedArgs.mountExternal, parsedArgs.seInfo,
parsedArgs.niceName, fdsToClose, parsedArgs.instructionSet,
parsedArgs.appDataDir);
} catch (ErrnoException ex) {
logAndPrintError(newStderr, “Exception creating pipe”, ex);
} catch (IllegalArgumentException ex) {
logAndPrintError(newStderr, “Invalid zygote arguments”, ex);
} catch (ZygoteSecurityException ex) {
logAndPrintError(newStderr,
"Zygote security policy prevents request: ", ex);
}

try {
//pid == 0时表示当前是在新创建的子进程重磅执行
if (pid == 0) {
// in child
IoUtils.closeQuietly(serverPipeFd);
serverPipeFd = null;
handleChildProc(parsedArgs, descriptors, childPipeFd, newStderr);

// should never get here, the child is expected to either
// throw ZygoteInit.MethodAndArgsCaller or exec().
return true;
}
// pid < 0表示创建新进程失败，pid