Download source file from: http://www.boost.org/users/history/version_1_64_0.html
tar -xzvf boost_1_64_0.tar.gz
cd boost_1_64_0
./bootstrap.sh --prefix=/usr/local
./b2
./b2 install

cd wt-x.y.z
mkdir build; cd build
cmake ..
make
make -C examples

// To install wt in /usr/local
sudo make install
sudo ldconfig

tyler@ubuntu16:~/Documents/primecoin-core-desktop-src$ ./src/primecoin-cli -rpcuser=user -rpcpassword=password getblocktemplate '{"capabilities":["longpoll", "coinbasetxn", "coinbasevalue"]}'
{
  "capabilities": [
    "proposal"
  ],
  "version": 536870912,
  "rules": [
  ],
  "vbavailable": {
  },
  "vbrequired": 0,
  "previousblockhash": "47124348127fb1d00daf5f1a62c1115fe8fc8a6226f91c042211834459d06567",
  "transactions": [
  ],
  "coinbaseaux": {
    "flags": ""
  },
  "coinbasevalue": 734000000,
  "longpollid": "47124348127fb1d00daf5f1a62c1115fe8fc8a6226f91c042211834459d06567230",
  "target": "0000000000000000000000000000000000000000002937b40000000000000000",
  "mintime": 1539164867,
  "mutable": [
    "time",
    "transactions",
    "prevblock"
  ],
  "noncerange": "00000000ffffffff",
  "sigoplimit": 20000,
  "sizelimit": 1000000,
  "curtime": 1539224387,
  "bits": "0ba937b4",
  "height": 2875236
}

./bootstrap
make
sudo make install

//  Create a new socket within our CZMQ context, replaces zmq_socket.
//  Use this to get automatic management of the socket at shutdown.
//  Note: SUB sockets do not automatically subscribe to everything; you
//  must set filters explicitly.
CZMQ_EXPORT void *  zsocket_new (zctx_t *self, int type);

//  Bind a socket to a formatted endpoint. If the port is specified as
//  '*', binds to any free port from ZSOCKET_DYNFROM to ZSOCKET_DYNTO
//  and returns the actual port number used. Otherwise asserts that the
//  bind succeeded with the specified port number. Always returns the
//  port number if successful.
CZMQ_EXPORT int zsocket_bind (void *self, const char *format, ...);

//  This is a stable class, and may not change except for emergencies. It
//  is provided in stable builds.
//  This class has draft methods, which may change over time. They are not
//  in stable releases, by default. Use --enable-drafts to enable.
// Actors get a pipe and arguments from caller
typedef void (zactor_fn) (
   zsock_t *pipe, void *args);

//  Create a new actor passing arbitrary arguments reference.
CZMQ_EXPORT zactor_t *
   zactor_new (zactor_fn task, void *args);

//  Destroy an actor.
CZMQ_EXPORT void
   zactor_destroy (zactor_t **self_p);

//  Send a zmsg message to the actor, take ownership of the message
//  and destroy when it has been sent.
CZMQ_EXPORT int
   zactor_send (zactor_t *self, zmsg_t **msg_p);

//  Receive a zmsg message from the actor. Returns NULL if the actor
//  was interrupted before the message could be received, or if there
//  was a timeout on the actor.
//  Caller owns return value and must destroy it when done.
CZMQ_EXPORT zmsg_t *
   zactor_recv (zactor_t *self);

//  Probe the supplied object, and report if it looks like a zactor_t.
CZMQ_EXPORT bool
   zactor_is (void *self);

//  Probe the supplied reference. If it looks like a zactor_t instance,
//  return the underlying libzmq actor handle; else if it looks like
//  a libzmq actor handle, return the supplied value.
CZMQ_EXPORT void *
   zactor_resolve (void *self);

//  Return the actor's zsock handle. Use this when you absolutely need
//  to work with the zsock instance rather than the actor.
CZMQ_EXPORT zsock_t *
   zactor_sock (zactor_t *self);

//  Self test of this class.
CZMQ_EXPORT void
   zactor_test (bool verbose);

#ifdef CZMQ_BUILD_DRAFT_API
// Function to be called on zactor_destroy. Default behavior is to send zmsg_t with string "$TERM" in a first frame.
//
// An example - to send $KTHXBAI string
//
//     if (zstr_send (self, "$KTHXBAI") == 0)
//         zsock_wait (self);
typedef void (zactor_destructor_fn) (
   zactor_t *self);

//  *** Draft method, for development use, may change without warning ***
//  Change default destructor by custom function. Actor MUST be able to handle new message instead of default $TERM.
CZMQ_EXPORT void
   zactor_set_destructor (zactor_t *self, zactor_destructor_fn destructor);

#endif // CZMQ_BUILD_DRAFT_API
Please add '@interface' section in './../src/zactor.c'.

//  Create an attached thread. An attached thread gets a ctx and a PAIR
//  pipe back to its parent. It must monitor its pipe, and exit if the
//  pipe becomes unreadable. Do not destroy the ctx, the thread does this
//  automatically when it ends.
CZMQ_EXPORT void * zthread_fork (zctx_t *ctx, zthread_attached_fn *thread_fn, void *args);

//  Wait on a signal. Use this to coordinate between threads, over
//  pipe pairs. Returns -1 on error, 0 on success.
CZMQ_EXPORT int zsocket_wait (void *self);

//  This port range is defined by IANA for dynamic or private ports
//  We use this when choosing a port for dynamic binding.
#define ZSOCKET_DYNFROM     0xc000
#define ZSOCKET_DYNTO       0xffff

//  Callback function for zero-copy methods
typedef void (zsocket_free_fn) (void *data, void *arg);



//  Destroy a socket within our CZMQ context, replaces zmq_close.
CZMQ_EXPORT void
    zsocket_destroy (zctx_t *ctx, void *self);


//  Unbind a socket from a formatted endpoint.
//  Returns 0 if OK, -1 if the endpoint was invalid or the function
//  isn't supported.
CZMQ_EXPORT int
    zsocket_unbind (void *self, const char *format, ...);

//  Connect a socket to a formatted endpoint
//  Returns 0 if OK, -1 if the endpoint was invalid.
CZMQ_EXPORT int
    zsocket_connect (void *self, const char *format, ...);

//  Disconnect a socket from a formatted endpoint
//  Returns 0 if OK, -1 if the endpoint was invalid or the function
//  isn't supported.
CZMQ_EXPORT int
    zsocket_disconnect (void *self, const char *format, ...);

//  Poll for input events on the socket. Returns TRUE if there is input
//  ready on the socket, else FALSE.
CZMQ_EXPORT bool
    zsocket_poll (void *self, int msecs);

//  Returns socket type as printable constant string
CZMQ_EXPORT const char *
    zsocket_type_str (void *self);

//  Send data over a socket as a single message frame.
//  Accepts these flags: ZFRAME_MORE and ZFRAME_DONTWAIT.
//  Returns -1 on error, 0 on success
CZMQ_EXPORT int
    zsocket_sendmem (void *self, const void *data, size_t size, int flags);

//  Send a signal over a socket. A signal is a zero-byte message.
//  Signals are used primarily between threads, over pipe sockets.
//  Returns -1 if there was an error sending the signal.
CZMQ_EXPORT int
    zsocket_signal (void *self);



//  Self test of this class
CZMQ_EXPORT void
    zsocket_test (bool verbose);

class Singleton {
public:
static Singleton* getInstance(){
    if (m_sInstance == 0)
    {
        m_sInstance = new Singleton();
    }
    return m_sInstance;
}
static void releaseInstance(){
    if(nullptr != m_sInstance)
    {
        delete m_sInstance;
        m_sInstance = nullptr;
    }
}

    /* more (non-static) functions here */

private:
    Singleton();                            // ctor hidden
    Singleton(Singleton const&);            // copy ctor hidden
    Singleton& operator=(Singleton const&){ return *m_sInstance; }; // assign op. hidden
    ~Singleton();                           // dtor hidden

    static Singleton* m_sInstance;
};

/* Null, because instance will be initialized on demand. */
Singleton* Singleton::m_sInstance = 0;

Singleton* Singleton::getInstance()
{
    if (m_sInstance == 0)
    {
        m_sInstance = new Singleton();
    }
    return m_sInstance;
}

Singleton::Singleton()
{}

int main()
{
    //new Singleton(); // Won't work
    Singleton* s = Singleton::getInstance(); // Ok
    Singleton* r = Singleton::getInstance();

    /* The addresses will be the same. */
    std::cout << s << std::endl;
    std::cout << r << std::endl;
}

SELECT u.datname  FROM pg_catalog.pg_database u where u.datname='rftDatabase';

if( (select 1 from pg_class where relname='test'::name and relkind='r') is null  ) then
/*你的代码*/
end if;

docker pull postgres

// start a postgres instance
docker run --name pool-postgres -p 5432:5432 -e POSTGRES_PASSWORD=password -d postgres

sudo apt-get install libreadline-dev
./configure
make
sudo make install
sudo adduser postgres
sudo mkdir /usr/local/pgsql/data
sudo chown postgres /usr/local/pgsql/data
su - postgres
/usr/local/pgsql/bin/initdb -D /usr/local/pgsql/data
/usr/local/pgsql/bin/postgres -D /usr/local/pgsql/data >logfile 2>&1 &
/usr/local/pgsql/bin/createdb test
/usr/local/pgsql/bin/psql test

PostgreSQL的开机自启动脚本位于PostgreSQL源码目录的contrib/start-scripts路径下
chmod a+x linux
cp linux /etc/init.d/postgresql
修改/etc/init.d/postgresql文件的两个变量
prefix设置为postgresql的安装路径：/xxx/pgsql
PGDATA设置为postgresql的数据目录路径：/xxx/pgsql/data

启动PostgreSQL服务
service postgresql start

设置postgresql服务开机自启动
sudo apt install sysv-rc-conf

sysv-rc-conf postgresql

su - postgres
/usr/local/pgsql/bin/pg_ctl -s -D /usr/local/pgsql/data start -w -t 120

void f(vector<int> &v)
{
  v[0];    // A
  v.at[0];  // B
}

vector<int> temlist;
temlist.assign(list.begin(), list.end());