{"id":4230,"date":"2020-04-06T00:36:02","date_gmt":"2020-04-05T16:36:02","guid":{"rendered":"https:\/\/damogame.cn\/wordpress\/?p=4230"},"modified":"2020-04-06T00:36:02","modified_gmt":"2020-04-05T16:36:02","slug":"c%e7%9a%84placement-new%e6%93%8d%e4%bd%9c","status":"publish","type":"post","link":"https:\/\/i007.cc\/wordpress\/archives\/4230","title":{"rendered":"C++\u7684placement new\u64cd\u4f5c"},"content":{"rendered":"<div class=\"rEsl9f\">\n<div class=\"_2mYfmT\">\n<div>\n<div class=\"s-dsoj\"><a href=\"https:\/\/www.jianshu.com\/p\/342e69e3b9d6\">\u539f\u6587\u5730\u5740<\/a><\/div>\n<div><\/div>\n<\/div>\n<\/div>\n<\/div>\n<article class=\"_2rhmJa\">C++\u7684placement new\u64cd\u4f5c<\/p>\n<p>\u4ec0\u4e48\u662fplacement new\u64cd\u4f5c<br \/>\n\u6211\u4eec\u77e5\u9053C++\u7684new\u64cd\u4f5c\u7b26\u4f1a\u521b\u5efa\u4e00\u4e2a\u5bf9\u8c61\uff0c\u4ed6\u5b8c\u6210\u4e24\u6b65\u64cd\u4f5c\uff1a<\/p>\n<ol>\n<li>\u5206\u914d\u5bf9\u8c61\u5185\u5b58\u3002<\/li>\n<li>\u8c03\u7528\u5bf9\u8c61\u7c7b\u7684\u6784\u9020\u51fd\u6570\u521b\u5efa\u5bf9\u8c61\u3002<\/li>\n<\/ol>\n<p>\u901a\u5e38\u5206\u914d\u7684\u5185\u5b58\u662f\u5728\u5806\u4e2d\u3002<\/p>\n<p>\u4f46\u662f\u6709\u4e9b\u573a\u666f\u4e0b\uff0c\u6211\u4eec\u9884\u5148\u5df2\u7ecf\u5206\u914d\u4e86\u5185\u5b58\uff0c\u60f3\u8981\u5728\u5df2\u77e5\u7684\u5185\u5b58\u4e0a\u521b\u5efa\u5bf9\u8c61\u600e\u4e48\u529e\u5462\uff1f\u5c31\u662f\u8bf4\u6211\u5c31\u8981\u4e00\u4e2a\u5bf9\u8c61\u521b\u5efa\u5728\u8fd9\u4e2a\u5185\u5b58\u5730\u5740\uff0cplacement new\u5c31\u662f\u5b9e\u73b0\u8fd9\u4e2a\u76ee\u7684\u7684\u3002\u5176\u8bed\u6cd5\uff1a<\/p>\n<div class=\"_2Uzcx_\"><button class=\"VJbwyy\" type=\"button\" aria-label=\"\u590d\u5236\u4ee3\u7801\"><i class=\"anticon anticon-copy\" aria-label=\"icon: copy\"><\/i><\/button><\/p>\n<pre class=\"line-numbers  language-dart\"><code class=\"  language-dart\">Object <span class=\"token operator\">*<\/span> p <span class=\"token operator\">=<\/span> <span class=\"token keyword\">new<\/span> <span class=\"token punctuation\">(<\/span>address<span class=\"token punctuation\">)<\/span> <span class=\"token function\">ClassConstruct<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">.<\/span><span class=\"token punctuation\">.<\/span><span class=\"token punctuation\">.<\/span><span class=\"token punctuation\">)<\/span>\r\n<\/code><\/pre>\n<\/div>\n<p>\u5e94\u7528\u573a\u666f<br \/>\n\u5728\u8fdb\u7a0b\u95f4\u4f7f\u7528\u5171\u4eab\u5185\u5b58\u7684\u65f6\u5019\uff0cC++\u7684placement new\u7ecf\u5e38\u88ab\u7528\u5230\u3002\u4f8b\u5982\u4e3b\u8fdb\u7a0b\u5206\u914d\u5171\u4eab\u5185\u5bb9\uff0c\u7136\u540e\u5728\u5171\u4eab\u5185\u5b58\u4e0a\u521b\u5efaC++\u7c7b\u5bf9\u8c61\uff0c\u7136\u540e\u4ece\u8fdb\u7a0b\u76f4\u63a5attach\u5230\u8fd9\u5757\u5171\u4eab\u5185\u5bb9\uff0c\u62ff\u5230\u7c7b\u5bf9\u8c61\uff0c\u76f4\u63a5\u8bbf\u95ee\u7c7b\u5bf9\u8c61\u7684\u53d8\u91cf\u548c\u51fd\u6570\u3002<\/p>\n<p>\u901a\u8fc7\u4e0b\u9762\u7684\u4f8b\u5b50\u6765\u8bf4\u660e\uff1a<\/p>\n<ol>\n<li>\u4e3b\u8fdb\u7a0b\u4ee5server\u7684\u65b9\u5f0f\u542f\u52a8\n<ul>\n<li>\u5206\u914d\u5171\u4eab\u5185\u5b58<\/li>\n<li>\u5728\u5171\u4eab\u5185\u5b58\u4e0a\u901a\u8fc7placement new\u521b\u5efa\u5bf9\u8c61SHMObj<\/li>\n<\/ul>\n<\/li>\n<li>\u4ece\u8fdb\u7a0b\u4ee5\u666e\u901a\u65b9\u5f0f\u542f\u52a8\n<ul>\n<li>attach\u5230\u4e3b\u8fdb\u7a0b\u7684\u5171\u4eab\u5185\u5b58<\/li>\n<li>\u62ff\u5230\u4ee3\u8868SHMObj\u5bf9\u8c61\u7684\u6307\u9488\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n<div class=\"_2Uzcx_\"><button class=\"VJbwyy\" type=\"button\" aria-label=\"\u590d\u5236\u4ee3\u7801\"><i class=\"anticon anticon-copy\" aria-label=\"icon: copy\"><\/i><\/button><\/p>\n<pre class=\"line-numbers  language-cpp\"><code class=\"  language-cpp\"><span class=\"token macro property\">#<span class=\"token directive keyword\">include<\/span> <span class=\"token string\">&lt;stdio.h&gt;<\/span><\/span>\r\n<span class=\"token macro property\">#<span class=\"token directive keyword\">include<\/span> <span class=\"token string\">&lt;stdlib.h&gt;<\/span><\/span>\r\n<span class=\"token macro property\">#<span class=\"token directive keyword\">include<\/span> <span class=\"token string\">&lt;string.h&gt;<\/span><\/span>\r\n<span class=\"token macro property\">#<span class=\"token directive keyword\">include<\/span> <span class=\"token string\">&lt;errno.h&gt;<\/span><\/span>\r\n\r\n<span class=\"token macro property\">#<span class=\"token directive keyword\">include<\/span> <span class=\"token string\">&lt;sys\/ipc.h&gt;<\/span><\/span>\r\n<span class=\"token macro property\">#<span class=\"token directive keyword\">include<\/span> <span class=\"token string\">&lt;sys\/shm.h&gt;<\/span><\/span>\r\n\r\n<span class=\"token macro property\">#<span class=\"token directive keyword\">include<\/span> <span class=\"token string\">&lt;new&gt;<\/span><\/span>\r\n\r\n<span class=\"token macro property\">#<span class=\"token directive keyword\">define<\/span> SHM_KEY 0x3887<\/span>\r\n\r\n<span class=\"token keyword\">class<\/span> <span class=\"token class-name\">SHMObj<\/span> <span class=\"token punctuation\">{<\/span>\r\n<span class=\"token keyword\">private<\/span><span class=\"token operator\">:<\/span>\r\n    <span class=\"token keyword\">int<\/span> count<span class=\"token punctuation\">;<\/span>\r\n<span class=\"token keyword\">public<\/span><span class=\"token operator\">:<\/span>\r\n    <span class=\"token function\">SHMObj<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token operator\">:<\/span> <span class=\"token function\">count<\/span><span class=\"token punctuation\">(<\/span><span class=\"token number\">100<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span><span class=\"token punctuation\">}<\/span>\r\n    <span class=\"token keyword\">void<\/span> <span class=\"token function\">increase<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span> count<span class=\"token operator\">++<\/span><span class=\"token punctuation\">;<\/span> <span class=\"token function\">print<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span> <span class=\"token punctuation\">}<\/span>\r\n    <span class=\"token keyword\">void<\/span> <span class=\"token function\">decrease<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span> count<span class=\"token operator\">--<\/span><span class=\"token punctuation\">;<\/span> <span class=\"token function\">print<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span> <span class=\"token punctuation\">}<\/span>\r\n    <span class=\"token keyword\">void<\/span> <span class=\"token function\">print<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span> <span class=\"token function\">printf<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">\"count=[%d]\\n\"<\/span><span class=\"token punctuation\">,<\/span> count<span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span> <span class=\"token punctuation\">}<\/span>\r\n<span class=\"token punctuation\">}<\/span><span class=\"token punctuation\">;<\/span>\r\n\r\n<span class=\"token keyword\">static<\/span> <span class=\"token keyword\">int<\/span>      shm_id <span class=\"token operator\">=<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">;<\/span>\r\n<span class=\"token keyword\">static<\/span> <span class=\"token keyword\">void<\/span> <span class=\"token operator\">*<\/span>   shm_addr <span class=\"token operator\">=<\/span> <span class=\"token constant\">NULL<\/span><span class=\"token punctuation\">;<\/span>\r\n<span class=\"token keyword\">static<\/span> SHMObj <span class=\"token operator\">*<\/span> shm_object <span class=\"token operator\">=<\/span> <span class=\"token constant\">NULL<\/span><span class=\"token punctuation\">;<\/span>\r\n\r\n<span class=\"token keyword\">static<\/span> <span class=\"token keyword\">int<\/span> <span class=\"token function\">attach<\/span><span class=\"token punctuation\">(<\/span><span class=\"token keyword\">bool<\/span> server<span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n    shm_id <span class=\"token operator\">=<\/span> <span class=\"token function\">shmget<\/span><span class=\"token punctuation\">(<\/span>SHM_KEY<span class=\"token punctuation\">,<\/span> <span class=\"token keyword\">sizeof<\/span><span class=\"token punctuation\">(<\/span>SHMObj<span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">,<\/span> server <span class=\"token operator\">?<\/span> <span class=\"token punctuation\">(<\/span>IPC_CREAT <span class=\"token operator\">|<\/span> <span class=\"token number\">0660<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token operator\">:<\/span> <span class=\"token number\">0660<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n    <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span>shm_id <span class=\"token operator\">&lt;<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n        <span class=\"token function\">printf<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">\"ERROR: attach(%d), errno=[%d],strerror=[%s]\\n\"<\/span><span class=\"token punctuation\">,<\/span> server<span class=\"token punctuation\">,<\/span> errno<span class=\"token punctuation\">,<\/span> <span class=\"token function\">strerror<\/span><span class=\"token punctuation\">(<\/span>errno<span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n        <span class=\"token keyword\">return<\/span> <span class=\"token operator\">-<\/span><span class=\"token number\">1<\/span><span class=\"token punctuation\">;<\/span>\r\n    <span class=\"token punctuation\">}<\/span>\r\n\r\n    <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">(<\/span>shm_addr <span class=\"token operator\">=<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token keyword\">struct<\/span> <span class=\"token class-name\">shm_content<\/span> <span class=\"token operator\">*<\/span><span class=\"token punctuation\">)<\/span><span class=\"token function\">shmat<\/span><span class=\"token punctuation\">(<\/span>shm_id<span class=\"token punctuation\">,<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token keyword\">void<\/span> <span class=\"token operator\">*<\/span><span class=\"token punctuation\">)<\/span><span class=\"token number\">0<\/span><span class=\"token punctuation\">,<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token operator\">==<\/span> <span class=\"token constant\">NULL<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n        <span class=\"token function\">printf<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">\"ERROR: attach(%d), errno=[%d],strerror=[%s]\\n\"<\/span><span class=\"token punctuation\">,<\/span> server<span class=\"token punctuation\">,<\/span> errno<span class=\"token punctuation\">,<\/span> <span class=\"token function\">strerror<\/span><span class=\"token punctuation\">(<\/span>errno<span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n        <span class=\"token keyword\">return<\/span> <span class=\"token operator\">-<\/span><span class=\"token number\">1<\/span><span class=\"token punctuation\">;<\/span>\r\n    <span class=\"token punctuation\">}<\/span>\r\n\r\n    <span class=\"token function\">printf<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">\"SUCC: attach(%d), key=[0x%x],id=[0x%x],address=[0x%x],object=[0x%x]\\n\"<\/span><span class=\"token punctuation\">,<\/span> server<span class=\"token punctuation\">,<\/span> SHM_KEY<span class=\"token punctuation\">,<\/span> shm_id<span class=\"token punctuation\">,<\/span> shm_addr<span class=\"token punctuation\">,<\/span> shm_object<span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n<span class=\"token punctuation\">}<\/span>\r\n\r\n<span class=\"token keyword\">static<\/span> <span class=\"token keyword\">int<\/span> <span class=\"token function\">dettach<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n    <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token function\">shmdt<\/span><span class=\"token punctuation\">(<\/span>shm_addr<span class=\"token punctuation\">)<\/span> <span class=\"token operator\">!=<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n        <span class=\"token function\">printf<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">\"ERROR: dettach(), errno=[%d],strerror=[%s]\\n\"<\/span><span class=\"token punctuation\">,<\/span> errno<span class=\"token punctuation\">,<\/span> <span class=\"token function\">strerror<\/span><span class=\"token punctuation\">(<\/span>errno<span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n        <span class=\"token keyword\">return<\/span> <span class=\"token operator\">-<\/span><span class=\"token number\">1<\/span><span class=\"token punctuation\">;<\/span>\r\n    <span class=\"token punctuation\">}<\/span>\r\n\r\n    <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token function\">shmctl<\/span><span class=\"token punctuation\">(<\/span>shm_id<span class=\"token punctuation\">,<\/span> IPC_RMID<span class=\"token punctuation\">,<\/span> <span class=\"token constant\">NULL<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token operator\">&lt;<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n        <span class=\"token function\">printf<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">\"ERROR: dettach(), errno=[%d],strerror=[%s]\\n\"<\/span><span class=\"token punctuation\">,<\/span> errno<span class=\"token punctuation\">,<\/span> <span class=\"token function\">strerror<\/span><span class=\"token punctuation\">(<\/span>errno<span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n        <span class=\"token keyword\">return<\/span> <span class=\"token operator\">-<\/span><span class=\"token number\">1<\/span><span class=\"token punctuation\">;<\/span>\r\n    <span class=\"token punctuation\">}<\/span>\r\n\r\n    <span class=\"token keyword\">return<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">;<\/span>\r\n<span class=\"token punctuation\">}<\/span>\r\n\r\n<span class=\"token keyword\">static<\/span> <span class=\"token keyword\">int<\/span> <span class=\"token function\">create<\/span><span class=\"token punctuation\">(<\/span><span class=\"token keyword\">bool<\/span> server<span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n    <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span>server<span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n        <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">(<\/span>shm_object <span class=\"token operator\">=<\/span> <span class=\"token keyword\">new<\/span> <span class=\"token punctuation\">(<\/span>shm_addr<span class=\"token punctuation\">)<\/span> <span class=\"token function\">SHMObj<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token operator\">==<\/span> <span class=\"token constant\">NULL<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n            <span class=\"token function\">printf<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">\"ERROR: attach(), errno=[%d],strerror=[%s]\\n\"<\/span><span class=\"token punctuation\">,<\/span> errno<span class=\"token punctuation\">,<\/span> <span class=\"token function\">strerror<\/span><span class=\"token punctuation\">(<\/span>errno<span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n            <span class=\"token keyword\">return<\/span> <span class=\"token operator\">-<\/span><span class=\"token number\">1<\/span><span class=\"token punctuation\">;<\/span>\r\n        <span class=\"token punctuation\">}<\/span>\r\n    <span class=\"token punctuation\">}<\/span>\r\n    <span class=\"token keyword\">else<\/span> <span class=\"token punctuation\">{<\/span>\r\n        <span class=\"token comment\">\/\/shm_object = (SHMObj *)(shm_addr);<\/span>\r\n        shm_object <span class=\"token operator\">=<\/span> <span class=\"token keyword\">reinterpret_cast<\/span><span class=\"token operator\">&lt;<\/span>SHMObj <span class=\"token operator\">*<\/span><span class=\"token operator\">&gt;<\/span><span class=\"token punctuation\">(<\/span>shm_addr<span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n    <span class=\"token punctuation\">}<\/span>\r\n    <span class=\"token function\">printf<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">\"SUCC: create(%d), address=[0x%x],object=[0x%x]\\n\"<\/span><span class=\"token punctuation\">,<\/span> server<span class=\"token punctuation\">,<\/span> shm_addr<span class=\"token punctuation\">,<\/span> shm_object<span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n    <span class=\"token keyword\">return<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">;<\/span>\r\n<span class=\"token punctuation\">}<\/span>\r\n\r\n<span class=\"token keyword\">static<\/span> <span class=\"token keyword\">int<\/span> <span class=\"token function\">increase<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n    <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span>shm_object <span class=\"token operator\">!=<\/span> <span class=\"token constant\">NULL<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n        shm_object<span class=\"token operator\">-&gt;<\/span><span class=\"token function\">increase<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n    <span class=\"token punctuation\">}<\/span>\r\n    <span class=\"token keyword\">else<\/span> <span class=\"token punctuation\">{<\/span>\r\n        <span class=\"token function\">printf<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">\"ERROR: increase(), call attach firstly\\n\"<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n    <span class=\"token punctuation\">}<\/span>\r\n<span class=\"token punctuation\">}<\/span>\r\n\r\n<span class=\"token keyword\">static<\/span> <span class=\"token keyword\">int<\/span> <span class=\"token function\">decrease<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n    <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span>shm_object <span class=\"token operator\">!=<\/span> <span class=\"token constant\">NULL<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n        shm_object<span class=\"token operator\">-&gt;<\/span><span class=\"token function\">decrease<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n    <span class=\"token punctuation\">}<\/span>\r\n    <span class=\"token keyword\">else<\/span> <span class=\"token punctuation\">{<\/span>\r\n        <span class=\"token function\">printf<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">\"ERROR: increase(), call attach firstly\\n\"<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n    <span class=\"token punctuation\">}<\/span>\r\n<span class=\"token punctuation\">}<\/span>\r\n\r\n<span class=\"token keyword\">static<\/span> <span class=\"token keyword\">int<\/span> <span class=\"token function\">print<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n    <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span>shm_object <span class=\"token operator\">!=<\/span> <span class=\"token constant\">NULL<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n        shm_object<span class=\"token operator\">-&gt;<\/span><span class=\"token function\">print<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n    <span class=\"token punctuation\">}<\/span>\r\n    <span class=\"token keyword\">else<\/span> <span class=\"token punctuation\">{<\/span>\r\n        <span class=\"token function\">printf<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">\"ERROR: print(), call attach firstly\\n\"<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n    <span class=\"token punctuation\">}<\/span>\r\n<span class=\"token punctuation\">}<\/span>\r\n\r\n<span class=\"token keyword\">void<\/span> <span class=\"token function\">help<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n    <span class=\"token function\">printf<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">\"attach  : \\n\"<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n    <span class=\"token function\">printf<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">\"dettach : \\n\"<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n    <span class=\"token function\">printf<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">\"create  : \\n\"<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n    <span class=\"token function\">printf<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">\"increase: \\n\"<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n    <span class=\"token function\">printf<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">\"decrease: \\n\"<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n    <span class=\"token function\">printf<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">\"print   : \\n\"<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n    <span class=\"token function\">printf<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">\"quit    : quit program\\n\"<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n<span class=\"token punctuation\">}<\/span>\r\n\r\n<span class=\"token keyword\">int<\/span> <span class=\"token function\">parseCommand<\/span><span class=\"token punctuation\">(<\/span><span class=\"token keyword\">char<\/span> <span class=\"token operator\">*<\/span> cmd<span class=\"token punctuation\">,<\/span> <span class=\"token keyword\">char<\/span> <span class=\"token operator\">*<\/span> argv<span class=\"token punctuation\">[<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n   <span class=\"token keyword\">const<\/span> <span class=\"token keyword\">char<\/span> sep<span class=\"token punctuation\">[<\/span><span class=\"token number\">3<\/span><span class=\"token punctuation\">]<\/span> <span class=\"token operator\">=<\/span> <span class=\"token string\">\" \\n\"<\/span><span class=\"token punctuation\">;<\/span>\r\n   <span class=\"token keyword\">char<\/span> <span class=\"token operator\">*<\/span>token <span class=\"token operator\">=<\/span> <span class=\"token function\">strtok<\/span><span class=\"token punctuation\">(<\/span>cmd<span class=\"token punctuation\">,<\/span> sep<span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n\r\n   <span class=\"token keyword\">int<\/span> i <span class=\"token operator\">=<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">;<\/span>\r\n   <span class=\"token keyword\">while<\/span> <span class=\"token punctuation\">(<\/span>token <span class=\"token operator\">!=<\/span> <span class=\"token constant\">NULL<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n      argv<span class=\"token punctuation\">[<\/span>i<span class=\"token operator\">++<\/span><span class=\"token punctuation\">]<\/span> <span class=\"token operator\">=<\/span> token<span class=\"token punctuation\">;<\/span>\r\n      token <span class=\"token operator\">=<\/span> <span class=\"token function\">strtok<\/span><span class=\"token punctuation\">(<\/span><span class=\"token constant\">NULL<\/span><span class=\"token punctuation\">,<\/span> sep<span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n   <span class=\"token punctuation\">}<\/span>\r\n    <span class=\"token keyword\">return<\/span> i<span class=\"token punctuation\">;<\/span>\r\n<span class=\"token punctuation\">}<\/span>\r\n\r\n<span class=\"token keyword\">int<\/span> <span class=\"token function\">main<\/span><span class=\"token punctuation\">(<\/span><span class=\"token keyword\">int<\/span> argc<span class=\"token punctuation\">,<\/span> <span class=\"token keyword\">char<\/span> <span class=\"token operator\">*<\/span> argv<span class=\"token punctuation\">[<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n    <span class=\"token keyword\">char<\/span> cmdbuffer<span class=\"token punctuation\">[<\/span><span class=\"token number\">1024<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">;<\/span>\r\n    <span class=\"token keyword\">char<\/span> <span class=\"token operator\">*<\/span> cmds<span class=\"token punctuation\">[<\/span><span class=\"token number\">10<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">;<\/span>    <span class=\"token comment\">\/** max parameters count *\/<\/span>\r\n    <span class=\"token keyword\">int<\/span> i <span class=\"token operator\">=<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">;<\/span>\r\n\r\n    <span class=\"token keyword\">while<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token number\">1<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n        <span class=\"token function\">printf<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">\"CMD&gt; \"<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n        <span class=\"token function\">fgets<\/span><span class=\"token punctuation\">(<\/span>cmdbuffer<span class=\"token punctuation\">,<\/span> <span class=\"token number\">1024<\/span><span class=\"token punctuation\">,<\/span> <span class=\"token constant\">stdin<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n        i <span class=\"token operator\">=<\/span> <span class=\"token function\">parseCommand<\/span><span class=\"token punctuation\">(<\/span>cmdbuffer<span class=\"token punctuation\">,<\/span> cmds<span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n        <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span>i <span class=\"token operator\">&gt;<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n            <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token function\">strcmp<\/span><span class=\"token punctuation\">(<\/span>cmds<span class=\"token punctuation\">[<\/span><span class=\"token number\">0<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">,<\/span> <span class=\"token string\">\"quit\"<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token operator\">==<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n                <span class=\"token keyword\">break<\/span><span class=\"token punctuation\">;<\/span>\r\n            <span class=\"token punctuation\">}<\/span>\r\n            <span class=\"token keyword\">else<\/span> <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token function\">strcmp<\/span><span class=\"token punctuation\">(<\/span>cmds<span class=\"token punctuation\">[<\/span><span class=\"token number\">0<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">,<\/span> <span class=\"token string\">\"attach\"<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token operator\">==<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n                    <span class=\"token function\">attach<\/span><span class=\"token punctuation\">(<\/span>argc <span class=\"token operator\">&gt;<\/span> <span class=\"token number\">1<\/span> <span class=\"token operator\">&amp;&amp;<\/span> <span class=\"token function\">strcmp<\/span><span class=\"token punctuation\">(<\/span>argv<span class=\"token punctuation\">[<\/span><span class=\"token number\">1<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">,<\/span><span class=\"token string\">\"server\"<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token operator\">==<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n            <span class=\"token punctuation\">}<\/span>\r\n            <span class=\"token keyword\">else<\/span> <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token function\">strcmp<\/span><span class=\"token punctuation\">(<\/span>cmds<span class=\"token punctuation\">[<\/span><span class=\"token number\">0<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">,<\/span> <span class=\"token string\">\"dettach\"<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token operator\">==<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n                    <span class=\"token function\">dettach<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n            <span class=\"token punctuation\">}<\/span>\r\n            <span class=\"token keyword\">else<\/span> <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token function\">strcmp<\/span><span class=\"token punctuation\">(<\/span>cmds<span class=\"token punctuation\">[<\/span><span class=\"token number\">0<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">,<\/span> <span class=\"token string\">\"create\"<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token operator\">==<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n                    <span class=\"token function\">create<\/span><span class=\"token punctuation\">(<\/span>argc <span class=\"token operator\">&gt;<\/span> <span class=\"token number\">1<\/span> <span class=\"token operator\">&amp;&amp;<\/span> <span class=\"token function\">strcmp<\/span><span class=\"token punctuation\">(<\/span>argv<span class=\"token punctuation\">[<\/span><span class=\"token number\">1<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">,<\/span><span class=\"token string\">\"server\"<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token operator\">==<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n            <span class=\"token punctuation\">}<\/span>\r\n            <span class=\"token keyword\">else<\/span> <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token function\">strcmp<\/span><span class=\"token punctuation\">(<\/span>cmds<span class=\"token punctuation\">[<\/span><span class=\"token number\">0<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">,<\/span> <span class=\"token string\">\"increase\"<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token operator\">==<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n                    <span class=\"token function\">increase<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n            <span class=\"token punctuation\">}<\/span>\r\n            <span class=\"token keyword\">else<\/span> <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token function\">strcmp<\/span><span class=\"token punctuation\">(<\/span>cmds<span class=\"token punctuation\">[<\/span><span class=\"token number\">0<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">,<\/span> <span class=\"token string\">\"decrease\"<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token operator\">==<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n                    <span class=\"token function\">decrease<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n            <span class=\"token punctuation\">}<\/span>\r\n            <span class=\"token keyword\">else<\/span> <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token function\">strcmp<\/span><span class=\"token punctuation\">(<\/span>cmds<span class=\"token punctuation\">[<\/span><span class=\"token number\">0<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">,<\/span> <span class=\"token string\">\"print\"<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token operator\">==<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n                    <span class=\"token function\">print<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n            <span class=\"token punctuation\">}<\/span>\r\n            <span class=\"token keyword\">else<\/span> <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token function\">strcmp<\/span><span class=\"token punctuation\">(<\/span>cmds<span class=\"token punctuation\">[<\/span><span class=\"token number\">0<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">,<\/span> <span class=\"token string\">\"help\"<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token operator\">==<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span>\r\n                <span class=\"token function\">help<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n            <span class=\"token punctuation\">}<\/span>\r\n            <span class=\"token keyword\">else<\/span> <span class=\"token punctuation\">{<\/span>\r\n                <span class=\"token function\">printf<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">\"unknown command: %s\\n\"<\/span><span class=\"token punctuation\">,<\/span> cmds<span class=\"token punctuation\">[<\/span><span class=\"token number\">0<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span>\r\n            <span class=\"token punctuation\">}<\/span>\r\n        <span class=\"token punctuation\">}<\/span>\r\n    <span class=\"token punctuation\">}<\/span>\r\n    <span class=\"token keyword\">return<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">;<\/span>\r\n<span class=\"token punctuation\">}<\/span>\r\n<\/code><\/pre>\n<\/div>\n<p>\u8fd0\u884c<br \/>\n\u4e3b\u8fdb\u7a0b\uff1a<\/p>\n<div class=\"_2Uzcx_\"><button class=\"VJbwyy\" type=\"button\" aria-label=\"\u590d\u5236\u4ee3\u7801\"><i class=\"anticon anticon-copy\" aria-label=\"icon: copy\"><\/i><\/button><\/p>\n<pre class=\"line-numbers  language-objectivec\"><code class=\"  language-objectivec\">$ <span class=\"token punctuation\">.<\/span><span class=\"token operator\">\/<\/span>main server\r\nCMD<span class=\"token operator\">&gt;<\/span> attach\r\nSUCC<span class=\"token punctuation\">:<\/span> <span class=\"token function\">attach<\/span><span class=\"token punctuation\">(<\/span><span class=\"token number\">1<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">,<\/span> key<span class=\"token operator\">=<\/span><span class=\"token punctuation\">[<\/span><span class=\"token number\">0x3887<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">,<\/span>id<span class=\"token operator\">=<\/span><span class=\"token punctuation\">[<\/span><span class=\"token number\">0x1a8004<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">,<\/span>address<span class=\"token operator\">=<\/span><span class=\"token punctuation\">[<\/span><span class=\"token number\">0xe7b59000<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">,<\/span>object<span class=\"token operator\">=<\/span><span class=\"token punctuation\">[<\/span><span class=\"token number\">0x0<\/span><span class=\"token punctuation\">]<\/span>\r\nCMD<span class=\"token operator\">&gt;<\/span> create\r\nSUCC<span class=\"token punctuation\">:<\/span> <span class=\"token function\">create<\/span><span class=\"token punctuation\">(<\/span><span class=\"token number\">1<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">,<\/span> address<span class=\"token operator\">=<\/span><span class=\"token punctuation\">[<\/span><span class=\"token number\">0xe7b59000<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">,<\/span>object<span class=\"token operator\">=<\/span><span class=\"token punctuation\">[<\/span><span class=\"token number\">0xe7b59000<\/span><span class=\"token punctuation\">]<\/span>\r\nCMD<span class=\"token operator\">&gt;<\/span> print\r\ncount<span class=\"token operator\">=<\/span><span class=\"token punctuation\">[<\/span><span class=\"token number\">100<\/span><span class=\"token punctuation\">]<\/span>\r\nCMD<span class=\"token operator\">&gt;<\/span> increase\r\ncount<span class=\"token operator\">=<\/span><span class=\"token punctuation\">[<\/span><span class=\"token number\">101<\/span><span class=\"token punctuation\">]<\/span>\r\nCMD<span class=\"token operator\">&gt;<\/span> increase\r\ncount<span class=\"token operator\">=<\/span><span class=\"token punctuation\">[<\/span><span class=\"token number\">102<\/span><span class=\"token punctuation\">]<\/span>\r\nCMD<span class=\"token operator\">&gt;<\/span> print\r\ncount<span class=\"token operator\">=<\/span><span class=\"token punctuation\">[<\/span><span class=\"token number\">102<\/span><span class=\"token punctuation\">]<\/span>\r\nCMD<span class=\"token operator\">&gt;<\/span> \r\n<\/code><\/pre>\n<\/div>\n<p>\u4ece\u8fdb\u7a0b\uff1a<\/p>\n<div class=\"_2Uzcx_\"><button class=\"VJbwyy\" type=\"button\" aria-label=\"\u590d\u5236\u4ee3\u7801\"><i class=\"anticon anticon-copy\" aria-label=\"icon: copy\"><\/i><\/button><\/p>\n<pre class=\"line-numbers  language-objectivec\"><code class=\"  language-objectivec\">$ <span class=\"token punctuation\">.<\/span><span class=\"token operator\">\/<\/span>main \r\nCMD<span class=\"token operator\">&gt;<\/span> attach\r\nSUCC<span class=\"token punctuation\">:<\/span> <span class=\"token function\">attach<\/span><span class=\"token punctuation\">(<\/span><span class=\"token number\">0<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">,<\/span> key<span class=\"token operator\">=<\/span><span class=\"token punctuation\">[<\/span><span class=\"token number\">0x3887<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">,<\/span>id<span class=\"token operator\">=<\/span><span class=\"token punctuation\">[<\/span><span class=\"token number\">0x1a8004<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">,<\/span>address<span class=\"token operator\">=<\/span><span class=\"token punctuation\">[<\/span><span class=\"token number\">0xa1126000<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">,<\/span>object<span class=\"token operator\">=<\/span><span class=\"token punctuation\">[<\/span><span class=\"token number\">0x0<\/span><span class=\"token punctuation\">]<\/span>\r\nCMD<span class=\"token operator\">&gt;<\/span> create\r\nSUCC<span class=\"token punctuation\">:<\/span> <span class=\"token function\">create<\/span><span class=\"token punctuation\">(<\/span><span class=\"token number\">0<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">,<\/span> address<span class=\"token operator\">=<\/span><span class=\"token punctuation\">[<\/span><span class=\"token number\">0xa1126000<\/span><span class=\"token punctuation\">]<\/span><span class=\"token punctuation\">,<\/span>object<span class=\"token operator\">=<\/span><span class=\"token punctuation\">[<\/span><span class=\"token number\">0xa1126000<\/span><span class=\"token punctuation\">]<\/span>\r\nCMD<span class=\"token operator\">&gt;<\/span> print\r\ncount<span class=\"token operator\">=<\/span><span class=\"token punctuation\">[<\/span><span class=\"token number\">102<\/span><span class=\"token punctuation\">]<\/span>\r\nCMD<span class=\"token operator\">&gt;<\/span> \r\n<\/code><\/pre>\n<\/div>\n<p>\u4ece\u8fd9\u4e2a\u4f8b\u5b50\u6211\u4eec\u770b\u5230\u5bf9\u8c61shm_object\u5728\u4e3b\u8fdb\u7a0b\u91cc\u9762\u88ab\u521b\u5efa(placement new)\uff0c\u4f46\u662f\u5728\u4ece\u8fdb\u7a0b\u91cc\u9762\u5e76\u6ca1\u6709\u521b\u5efa\uff0c\u800c\u662f\u76f4\u63a5\u4ece\u5171\u4eab\u5185\u5b58\u91cc\u9762\u89e3\u6790\u51fa\u6765\uff0c\u7136\u540e\u76f4\u63a5\u8bbf\u95ee\u7c7b\u6210\u5458\u548c\u51fd\u6570\u3002<br \/>\n\u9700\u8981\u6ce8\u610f\u7684\u662f\uff0c\u521b\u5efa\u51fa\u6765\u7684\u5bf9\u8c61\u7684\u5730\u5740\u5c31\u662f\u5171\u4eab\u5185\u5b58\u7684\u5730\u5740\uff0c\u5c31\u662f\u57fa\u4e8e\u8fd9\u4e2a\u5c5e\u6027\uff0c\u6211\u4eec\u7684\u529f\u80fd\u624d\u80fd\u5b9e\u73b0\u3002\u4e5f\u5c31\u662f\u8bf4\uff1a<\/p>\n<div class=\"_2Uzcx_\"><button class=\"VJbwyy\" type=\"button\" aria-label=\"\u590d\u5236\u4ee3\u7801\"><i class=\"anticon anticon-copy\" aria-label=\"icon: copy\"><\/i><\/button><\/p>\n<pre class=\"line-numbers  language-dart\"><code class=\"  language-dart\">Object <span class=\"token operator\">*<\/span> p <span class=\"token operator\">=<\/span> <span class=\"token keyword\">new<\/span> <span class=\"token punctuation\">(<\/span>address<span class=\"token punctuation\">)<\/span> <span class=\"token function\">ClassConstruct<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">.<\/span><span class=\"token punctuation\">.<\/span><span class=\"token punctuation\">.<\/span><span class=\"token punctuation\">)<\/span>\r\n<\/code><\/pre>\n<\/div>\n<p>\u8fd4\u56dep\u7684\u503c\uff0c\u548c\u8f93\u5165\u5730\u5740address\u7684\u503c\u662f\u76f8\u540c\u7684\u3002<\/p>\n<\/article>\n","protected":false},"excerpt":{"rendered":"<p>\u539f\u6587\u5730\u5740 C++\u7684placement n<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"colormag_page_container_layout":"default_layout","colormag_page_sidebar_layout":"default_layout","footnotes":""},"categories":[],"tags":[119],"class_list":["post-4230","post","type-post","status-publish","format-standard","hentry","tag-03-"],"_links":{"self":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/4230","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/comments?post=4230"}],"version-history":[{"count":0,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/4230\/revisions"}],"wp:attachment":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/media?parent=4230"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/categories?post=4230"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/tags?post=4230"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}