{"id":580,"date":"2017-10-19T18:15:20","date_gmt":"2017-10-19T10:15:20","guid":{"rendered":"https:\/\/i007.cc\/wordpress\/?p=580"},"modified":"2017-11-24T15:17:14","modified_gmt":"2017-11-24T07:17:14","slug":"linux%e4%b8%adfork%ef%bc%88%ef%bc%89%e5%87%bd%e6%95%b0%e8%af%a6%e8%a7%a3%ef%bc%88%e5%8e%9f%e5%88%9b%ef%bc%81%ef%bc%81%e5%ae%9e%e4%be%8b%e8%ae%b2%e8%a7%a3%ef%bc%89","status":"publish","type":"post","link":"https:\/\/i007.cc\/wordpress\/archives\/580","title":{"rendered":"linux\u4e2dfork\uff08\uff09\u51fd\u6570\u8be6\u89e3\uff08\u539f\u521b\uff01\uff01\u5b9e\u4f8b\u8bb2\u89e3\uff09"},"content":{"rendered":"

\u00a0\u6807\u7b7e\uff1a\u00a0linux<\/a>2010<\/a>\u5b58\u50a8<\/a><\/p>\n

2010-06-01 23:35\u00a0261252\u4eba\u9605\u8bfb\u00a0\u8bc4\u8bba<\/a>(166)\u00a0\u6536\u85cf<\/span>\u00a0\u4e3e\u62a5<\/a><\/p>\n

\u5206\u7c7b\uff1a<\/p>\n

linux\u00a0\u8ba1\u7b97\u673a\u7cfb\u7edf<\/p>\n

\u7248\u6743\u58f0\u660e\uff1a\u672c\u6587\u4e3a\u535a\u4e3b\u539f\u521b\u6587\u7ae0\uff0c\u672a\u7ecf\u535a\u4e3b\u5141\u8bb8\u4e0d\u5f97\u8f6c\u8f7d\u3002<\/p>\n

\u00a0\u4e00\u3001fork\u5165\u95e8\u77e5\u8bc6<\/strong><\/p>\n

\u4e00\u4e2a\u8fdb\u7a0b\uff0c\u5305\u62ec\u4ee3\u7801\u3001\u6570\u636e\u548c\u5206\u914d\u7ed9\u8fdb\u7a0b\u7684\u8d44\u6e90\u3002fork\uff08\uff09\u51fd\u6570\u901a\u8fc7\u7cfb\u7edf\u8c03\u7528\u521b\u5efa\u4e00\u4e2a\u4e0e\u539f\u6765\u8fdb\u7a0b\u51e0\u4e4e\u5b8c\u5168\u76f8\u540c\u7684\u8fdb\u7a0b\uff0c\u4e5f\u5c31\u662f\u4e24\u4e2a\u8fdb\u7a0b\u53ef\u4ee5\u505a\u5b8c\u5168\u76f8\u540c\u7684\u4e8b\uff0c\u4f46\u5982\u679c\u521d\u59cb\u53c2\u6570\u6216\u8005\u4f20\u5165\u7684\u53d8\u91cf\u4e0d\u540c\uff0c\u4e24\u4e2a\u8fdb\u7a0b\u4e5f\u53ef\u4ee5\u505a\u4e0d\u540c\u7684\u4e8b\u3002
\n\u4e00\u4e2a\u8fdb\u7a0b\u8c03\u7528fork\uff08\uff09\u51fd\u6570\u540e\uff0c\u7cfb\u7edf\u5148\u7ed9\u65b0\u7684\u8fdb\u7a0b\u5206\u914d\u8d44\u6e90\uff0c\u4f8b\u5982\u5b58\u50a8\u6570\u636e\u548c\u4ee3\u7801\u7684\u7a7a\u95f4\u3002\u7136\u540e\u628a\u539f\u6765\u7684\u8fdb\u7a0b\u7684\u6240\u6709\u503c\u90fd\u590d\u5236\u5230\u65b0\u7684\u65b0\u8fdb\u7a0b\u4e2d\uff0c\u53ea\u6709\u5c11\u6570\u503c\u4e0e\u539f\u6765\u7684\u8fdb\u7a0b\u7684\u503c\u4e0d\u540c\u3002\u76f8\u5f53\u4e8e\u514b\u9686\u4e86\u4e00\u4e2a\u81ea\u5df1\u3002<\/p>\n

\u6211\u4eec\u6765\u770b\u4e00\u4e2a\u4f8b\u5b50\uff1a<\/p>\n

[cpp]<\/strong>\u00a0view plain<\/a>\u00a0copy<\/a><\/span><\/p>\n

    \n
  1. \/*<\/li>\n
  2. \u00a0*\u00a0\u00a0fork_test.c<\/li>\n
  3. \u00a0*\u00a0\u00a0version\u00a01<\/li>\n
  4. \u00a0*\u00a0\u00a0Created\u00a0on:\u00a02010-5-29<\/li>\n
  5. \u00a0*\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0Author:\u00a0wangth<\/li>\n
  6. \u00a0*\/<\/li>\n
  7. #include\u00a0<unistd.h><\/li>\n
  8. #include\u00a0<stdio.h><\/li>\n
  9. int<\/b>\u00a0main\u00a0()<\/li>\n
  10. {<\/li>\n
  11. \u00a0\u00a0\u00a0\u00a0pid_t\u00a0fpid;\u00a0\/\/fpid\u8868\u793afork\u51fd\u6570\u8fd4\u56de\u7684\u503c<\/li>\n
  12. \u00a0\u00a0\u00a0\u00a0int<\/b>\u00a0count=0;<\/li>\n
  13. \u00a0\u00a0\u00a0\u00a0fpid=fork();<\/li>\n
  14. \u00a0\u00a0\u00a0\u00a0if<\/b>\u00a0(fpid\u00a0<\u00a00)<\/li>\n
  15. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0printf(“error\u00a0in\u00a0fork!”);<\/li>\n
  16. \u00a0\u00a0\u00a0\u00a0else<\/b>\u00a0if<\/b>\u00a0(fpid\u00a0==\u00a00)\u00a0{<\/li>\n
  17. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0printf(“i\u00a0am\u00a0the\u00a0child\u00a0process,\u00a0my\u00a0process\u00a0id\u00a0is\u00a0%d\/n”,getpid());<\/li>\n
  18. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0printf(“\u6211\u662f\u7239\u7684\u513f\u5b50\/n”);\/\/\u5bf9\u67d0\u4e9b\u4eba\u6765\u8bf4\u4e2d\u6587\u770b\u7740\u66f4\u76f4\u767d\u3002<\/li>\n
  19. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0count++;<\/li>\n
  20. \u00a0\u00a0\u00a0\u00a0}<\/li>\n
  21. \u00a0\u00a0\u00a0\u00a0else<\/b>\u00a0{<\/li>\n
  22. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0printf(“i\u00a0am\u00a0the\u00a0parent\u00a0process,\u00a0my\u00a0process\u00a0id\u00a0is\u00a0%d\/n”,getpid());<\/li>\n
  23. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0printf(“\u6211\u662f\u5b69\u5b50\u4ed6\u7239\/n”);<\/li>\n
  24. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0count++;<\/li>\n
  25. \u00a0\u00a0\u00a0\u00a0}<\/li>\n
  26. \u00a0\u00a0\u00a0\u00a0printf(“\u7edf\u8ba1\u7ed3\u679c\u662f:\u00a0%d\/n”,count);<\/li>\n
  27. \u00a0\u00a0\u00a0\u00a0return<\/b>\u00a00;<\/li>\n
  28. }<\/li>\n<\/ol>\n

    \u8fd0\u884c\u7ed3\u679c\u662f\uff1a
    \ni am the child process, my process id is 5574
    \n\u6211\u662f\u7239\u7684\u513f\u5b50
    \n\u7edf\u8ba1\u7ed3\u679c\u662f: 1
    \ni am the parent process, my process id is 5573
    \n\u6211\u662f\u5b69\u5b50\u4ed6\u7239
    \n\u7edf\u8ba1\u7ed3\u679c\u662f: 1
    \n\u5728\u8bed\u53e5fpid=fork()\u4e4b\u524d\uff0c\u53ea\u6709\u4e00\u4e2a\u8fdb\u7a0b\u5728\u6267\u884c\u8fd9\u6bb5\u4ee3\u7801\uff0c\u4f46\u5728\u8fd9\u6761\u8bed\u53e5\u4e4b\u540e\uff0c\u5c31\u53d8\u6210\u4e24\u4e2a\u8fdb\u7a0b\u5728\u6267\u884c\u4e86\uff0c\u8fd9\u4e24\u4e2a\u8fdb\u7a0b\u7684\u51e0\u4e4e\u5b8c\u5168\u76f8\u540c\uff0c\u5c06\u8981\u6267\u884c\u7684\u4e0b\u4e00\u6761\u8bed\u53e5\u90fd\u662fif(fpid<0)\u2026\u2026
    \n\u4e3a\u4ec0\u4e48\u4e24\u4e2a\u8fdb\u7a0b\u7684fpid\u4e0d\u540c\u5462\uff0c\u8fd9\u4e0efork\u51fd\u6570\u7684\u7279\u6027\u6709\u5173\u3002fork\u8c03\u7528\u7684\u4e00\u4e2a\u5947\u5999\u4e4b\u5904\u5c31\u662f\u5b83\u4ec5\u4ec5\u88ab\u8c03\u7528\u4e00\u6b21\uff0c\u5374\u80fd\u591f\u8fd4\u56de\u4e24\u6b21\uff0c\u5b83\u53ef\u80fd\u6709\u4e09\u79cd\u4e0d\u540c\u7684\u8fd4\u56de\u503c\uff1a
    \n1\uff09\u5728\u7236\u8fdb\u7a0b\u4e2d\uff0cfork\u8fd4\u56de\u65b0\u521b\u5efa\u5b50\u8fdb\u7a0b\u7684\u8fdb\u7a0bID\uff1b
    \n2\uff09\u5728\u5b50\u8fdb\u7a0b\u4e2d\uff0cfork\u8fd4\u56de0\uff1b
    \n3\uff09\u5982\u679c\u51fa\u73b0\u9519\u8bef\uff0cfork\u8fd4\u56de\u4e00\u4e2a\u8d1f\u503c\uff1b<\/p>\n

    \u5728fork\u51fd\u6570\u6267\u884c\u5b8c\u6bd5\u540e\uff0c\u5982\u679c\u521b\u5efa\u65b0\u8fdb\u7a0b\u6210\u529f\uff0c\u5219\u51fa\u73b0\u4e24\u4e2a\u8fdb\u7a0b\uff0c\u4e00\u4e2a\u662f\u5b50\u8fdb\u7a0b\uff0c\u4e00\u4e2a\u662f\u7236\u8fdb\u7a0b\u3002\u5728\u5b50\u8fdb\u7a0b\u4e2d\uff0cfork\u51fd\u6570\u8fd4\u56de0\uff0c\u5728\u7236\u8fdb\u7a0b\u4e2d\uff0cfork\u8fd4\u56de\u65b0\u521b\u5efa\u5b50\u8fdb\u7a0b\u7684\u8fdb\u7a0bID\u3002\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7fork\u8fd4\u56de\u7684\u503c\u6765\u5224\u65ad\u5f53\u524d\u8fdb\u7a0b\u662f\u5b50\u8fdb\u7a0b\u8fd8\u662f\u7236\u8fdb\u7a0b\u3002<\/p>\n

    \u5f15\u7528\u4e00\u4f4d\u7f51\u53cb\u7684\u8bdd\u6765\u89e3\u91cafpid\u7684\u503c\u4e3a\u4ec0\u4e48\u5728\u7236\u5b50\u8fdb\u7a0b\u4e2d\u4e0d\u540c\u3002\u201c\u5176\u5b9e\u5c31\u76f8\u5f53\u4e8e\u94fe\u8868\uff0c\u8fdb\u7a0b\u5f62\u6210\u4e86\u94fe\u8868\uff0c\u7236\u8fdb\u7a0b\u7684fpid(p \u610f\u5473point)\u6307\u5411\u5b50\u8fdb\u7a0b\u7684\u8fdb\u7a0bid, \u56e0\u4e3a\u5b50\u8fdb\u7a0b\u6ca1\u6709\u5b50\u8fdb\u7a0b\uff0c\u6240\u4ee5\u5176fpid\u4e3a0.
    \nfork\u51fa\u9519\u53ef\u80fd\u6709\u4e24\u79cd\u539f\u56e0\uff1a
    \n1\uff09\u5f53\u524d\u7684\u8fdb\u7a0b\u6570\u5df2\u7ecf\u8fbe\u5230\u4e86\u7cfb\u7edf\u89c4\u5b9a\u7684\u4e0a\u9650\uff0c\u8fd9\u65f6errno\u7684\u503c\u88ab\u8bbe\u7f6e\u4e3aEAGAIN\u3002
    \n2\uff09\u7cfb\u7edf\u5185\u5b58\u4e0d\u8db3\uff0c\u8fd9\u65f6errno\u7684\u503c\u88ab\u8bbe\u7f6e\u4e3aENOMEM\u3002
    \n\u521b\u5efa\u65b0\u8fdb\u7a0b\u6210\u529f\u540e\uff0c\u7cfb\u7edf\u4e2d\u51fa\u73b0\u4e24\u4e2a\u57fa\u672c\u5b8c\u5168\u76f8\u540c\u7684\u8fdb\u7a0b\uff0c\u8fd9\u4e24\u4e2a\u8fdb\u7a0b\u6267\u884c\u6ca1\u6709\u56fa\u5b9a\u7684\u5148\u540e\u987a\u5e8f\uff0c\u54ea\u4e2a\u8fdb\u7a0b\u5148\u6267\u884c\u8981\u770b\u7cfb\u7edf\u7684\u8fdb\u7a0b\u8c03\u5ea6\u7b56\u7565\u3002
    \n\u6bcf\u4e2a\u8fdb\u7a0b\u90fd\u6709\u4e00\u4e2a\u72ec\u7279\uff08\u4e92\u4e0d\u76f8\u540c\uff09\u7684\u8fdb\u7a0b\u6807\u8bc6\u7b26\uff08process ID\uff09\uff0c\u53ef\u4ee5\u901a\u8fc7getpid\uff08\uff09\u51fd\u6570\u83b7\u5f97\uff0c\u8fd8\u6709\u4e00\u4e2a\u8bb0\u5f55\u7236\u8fdb\u7a0bpid\u7684\u53d8\u91cf\uff0c\u53ef\u4ee5\u901a\u8fc7getppid\uff08\uff09\u51fd\u6570\u83b7\u5f97\u53d8\u91cf\u7684\u503c\u3002
    \nfork\u6267\u884c\u5b8c\u6bd5\u540e\uff0c\u51fa\u73b0\u4e24\u4e2a\u8fdb\u7a0b\uff0c<\/p>\n

    \u6709\u4eba\u8bf4\u4e24\u4e2a\u8fdb\u7a0b\u7684\u5185\u5bb9\u5b8c\u5168\u4e00\u6837\u554a\uff0c\u600e\u4e48\u6253\u5370\u7684\u7ed3\u679c\u4e0d\u4e00\u6837\u554a\uff0c\u90a3\u662f\u56e0\u4e3a\u5224\u65ad\u6761\u4ef6\u7684\u539f\u56e0\uff0c\u4e0a\u9762\u5217\u4e3e\u7684\u53ea\u662f\u8fdb\u7a0b\u7684\u4ee3\u7801\u548c\u6307\u4ee4\uff0c\u8fd8\u6709\u53d8\u91cf\u554a\u3002
    \n\u6267\u884c\u5b8cfork\u540e\uff0c\u8fdb\u7a0b1\u7684\u53d8\u91cf\u4e3acount=0\uff0cfpid\uff01=0\uff08\u7236\u8fdb\u7a0b\uff09\u3002\u8fdb\u7a0b2\u7684\u53d8\u91cf\u4e3acount=0\uff0cfpid=0\uff08\u5b50\u8fdb\u7a0b\uff09\uff0c\u8fd9\u4e24\u4e2a\u8fdb\u7a0b\u7684\u53d8\u91cf\u90fd\u662f\u72ec\u7acb\u7684\uff0c\u5b58\u5728\u4e0d\u540c\u7684\u5730\u5740\u4e2d\uff0c\u4e0d\u662f\u5171\u7528\u7684\uff0c\u8fd9\u70b9\u8981\u6ce8\u610f\u3002\u53ef\u4ee5\u8bf4\uff0c\u6211\u4eec\u5c31\u662f\u901a\u8fc7fpid\u6765\u8bc6\u522b\u548c\u64cd\u4f5c\u7236\u5b50\u8fdb\u7a0b\u7684\u3002
    \n\u8fd8\u6709\u4eba\u53ef\u80fd\u7591\u60d1\u4e3a\u4ec0\u4e48\u4e0d\u662f\u4ece#include\u5904\u5f00\u59cb\u590d\u5236\u4ee3\u7801\u7684\uff0c\u8fd9\u662f\u56e0\u4e3afork\u662f\u628a\u8fdb\u7a0b\u5f53\u524d\u7684\u60c5\u51b5\u62f7\u8d1d\u4e00\u4efd\uff0c\u6267\u884cfork\u65f6\uff0c\u8fdb\u7a0b\u5df2\u7ecf\u6267\u884c\u5b8c\u4e86int count=0;fork\u53ea\u62f7\u8d1d\u4e0b\u4e00\u4e2a\u8981\u6267\u884c\u7684\u4ee3\u7801\u5230\u65b0\u7684\u8fdb\u7a0b\u3002<\/p>\n

    \u4e8c\u3001fork\u8fdb\u9636\u77e5\u8bc6<\/strong><\/p>\n

    \u5148\u770b\u4e00\u4efd\u4ee3\u7801\uff1a<\/p>\n

    [cpp]<\/strong>\u00a0view plain<\/a>\u00a0copy<\/a><\/span><\/p>\n

      \n
    1. \/*<\/li>\n
    2. \u00a0*\u00a0\u00a0fork_test.c<\/li>\n
    3. \u00a0*\u00a0\u00a0version\u00a02<\/li>\n
    4. \u00a0*\u00a0\u00a0Created\u00a0on:\u00a02010-5-29<\/li>\n
    5. \u00a0*\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0Author:\u00a0wangth<\/li>\n
    6. \u00a0*\/<\/li>\n
    7. #include\u00a0<unistd.h><\/li>\n
    8. #include\u00a0<stdio.h><\/li>\n
    9. int<\/b>\u00a0main(void<\/b>)<\/li>\n
    10. {<\/li>\n
    11. \u00a0\u00a0\u00a0int<\/b>\u00a0i=0;<\/li>\n
    12. \u00a0\u00a0\u00a0printf(“i\u00a0son\/pa\u00a0ppid\u00a0pid\u00a0\u00a0fpid\/n”);<\/li>\n
    13. \u00a0\u00a0\u00a0\/\/ppid\u6307\u5f53\u524d\u8fdb\u7a0b\u7684\u7236\u8fdb\u7a0bpid<\/li>\n
    14. \u00a0\u00a0\u00a0\/\/pid\u6307\u5f53\u524d\u8fdb\u7a0b\u7684pid,<\/li>\n
    15. \u00a0\u00a0\u00a0\/\/fpid\u6307fork\u8fd4\u56de\u7ed9\u5f53\u524d\u8fdb\u7a0b\u7684\u503c<\/li>\n
    16. \u00a0\u00a0\u00a0for<\/b>(i=0;i<2;i++){<\/li>\n
    17. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0pid_t\u00a0fpid=fork();<\/li>\n
    18. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0if<\/b>(fpid==0)<\/li>\n
    19. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0printf(“%d\u00a0child\u00a0\u00a0%4d\u00a0%4d\u00a0%4d\/n”,i,getppid(),getpid(),fpid);<\/li>\n
    20. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0else<\/b><\/li>\n
    21. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0printf(“%d\u00a0parent\u00a0%4d\u00a0%4d\u00a0%4d\/n”,i,getppid(),getpid(),fpid);<\/li>\n
    22. \u00a0\u00a0\u00a0}<\/li>\n
    23. \u00a0\u00a0\u00a0return<\/b>\u00a00;<\/li>\n
    24. }<\/li>\n<\/ol>\n

      \u8fd0\u884c\u7ed3\u679c\u662f\uff1a
      \ni son\/pa ppid pid\u00a0 fpid
      \n0 parent 2043 3224 3225
      \n0 child\u00a0 3224 3225\u00a0\u00a0\u00a0 0
      \n1 parent 2043 3224 3226
      \n1 parent 3224 3225 3227
      \n1 child\u00a0\u00a0\u00a0\u00a0 1 3227\u00a0\u00a0\u00a0 0
      \n1 child\u00a0\u00a0\u00a0\u00a0 1 3226\u00a0\u00a0\u00a0 0
      \n\u8fd9\u4efd\u4ee3\u7801\u6bd4\u8f83\u6709\u610f\u601d\uff0c\u6211\u4eec\u6765\u8ba4\u771f\u5206\u6790\u4e00\u4e0b\uff1a
      \n\u7b2c\u4e00\u6b65\uff1a\u5728\u7236\u8fdb\u7a0b\u4e2d\uff0c\u6307\u4ee4\u6267\u884c\u5230for\u5faa\u73af\u4e2d\uff0ci=0\uff0c\u63a5\u7740\u6267\u884cfork\uff0cfork\u6267\u884c\u5b8c\u540e\uff0c\u7cfb\u7edf\u4e2d\u51fa\u73b0\u4e24\u4e2a\u8fdb\u7a0b\uff0c\u5206\u522b\u662fp3224\u548cp3225\uff08\u540e\u9762\u6211\u90fd\u7528pxxxx\u8868\u793a\u8fdb\u7a0bid\u4e3axxxx\u7684\u8fdb\u7a0b\uff09\u3002\u53ef\u4ee5\u770b\u5230\u7236\u8fdb\u7a0bp3224\u7684\u7236\u8fdb\u7a0b\u662fp2043\uff0c\u5b50\u8fdb\u7a0bp3225\u7684\u7236\u8fdb\u7a0b\u6b63\u597d\u662fp3224\u3002\u6211\u4eec\u7528\u4e00\u4e2a\u94fe\u8868\u6765\u8868\u793a\u8fd9\u4e2a\u5173\u7cfb\uff1a
      \np2043->p3224->p3225
      \n\u7b2c\u4e00\u6b21fork\u540e\uff0cp3224\uff08\u7236\u8fdb\u7a0b\uff09\u7684\u53d8\u91cf\u4e3ai=0\uff0cfpid=3225\uff08fork\u51fd\u6570\u5728\u7236\u8fdb\u7a0b\u4e2d\u8fd4\u5411\u5b50\u8fdb\u7a0bid\uff09\uff0c\u4ee3\u7801\u5185\u5bb9\u4e3a\uff1a<\/p>\n

      [c-sharp]<\/strong>\u00a0view plain<\/a>\u00a0copy<\/a><\/span><\/p>\n

        \n
      1. for<\/b>(i=0;i<2;i++){<\/li>\n
      2. \u00a0\u00a0\u00a0\u00a0pid_t\u00a0fpid=fork();\/\/\u6267\u884c\u5b8c\u6bd5\uff0ci=0\uff0cfpid=3225<\/li>\n
      3. \u00a0\u00a0\u00a0\u00a0if<\/b>(fpid==0)<\/li>\n
      4. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0printf(“%d\u00a0child\u00a0\u00a0%4d\u00a0%4d\u00a0%4d\/n”,i,getppid(),getpid(),fpid);<\/li>\n
      5. \u00a0\u00a0\u00a0\u00a0else<\/b><\/li>\n
      6. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0printf(“%d\u00a0parent\u00a0%4d\u00a0%4d\u00a0%4d\/n”,i,getppid(),getpid(),fpid);<\/li>\n
      7. }<\/li>\n
      8. return<\/b>\u00a00;<\/li>\n<\/ol>\n

        p3225\uff08\u5b50\u8fdb\u7a0b\uff09\u7684\u53d8\u91cf\u4e3ai=0\uff0cfpid=0\uff08fork\u51fd\u6570\u5728\u5b50\u8fdb\u7a0b\u4e2d\u8fd4\u56de0\uff09\uff0c\u4ee3\u7801\u5185\u5bb9\u4e3a\uff1a<\/p>\n

        [c-sharp]<\/strong>\u00a0view plain<\/a>\u00a0copy<\/a><\/span><\/p>\n

          \n
        1. for<\/b>(i=0;i<2;i++){<\/li>\n
        2. \u00a0\u00a0\u00a0\u00a0pid_t\u00a0fpid=fork();\/\/\u6267\u884c\u5b8c\u6bd5\uff0ci=0\uff0cfpid=0<\/li>\n
        3. \u00a0\u00a0\u00a0\u00a0if<\/b>(fpid==0)<\/li>\n
        4. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0printf(“%d\u00a0child\u00a0\u00a0%4d\u00a0%4d\u00a0%4d\/n”,i,getppid(),getpid(),fpid);<\/li>\n
        5. \u00a0\u00a0\u00a0\u00a0else<\/b><\/li>\n
        6. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0printf(“%d\u00a0parent\u00a0%4d\u00a0%4d\u00a0%4d\/n”,i,getppid(),getpid(),fpid);<\/li>\n
        7. }<\/li>\n
        8. return<\/b>\u00a00;<\/li>\n<\/ol>\n

          \u6240\u4ee5\u6253\u5370\u51fa\u7ed3\u679c\uff1a
          \n0\u00a0parent 2043 3224 3225
          \n0 child\u00a0 3224 3225\u00a0\u00a0\u00a0 0
          \n\u7b2c\u4e8c\u6b65\uff1a\u5047\u8bbe\u7236\u8fdb\u7a0bp3224\u5148\u6267\u884c\uff0c\u5f53\u8fdb\u5165\u4e0b\u4e00\u4e2a\u5faa\u73af\u65f6\uff0ci=1\uff0c\u63a5\u7740\u6267\u884cfork\uff0c\u7cfb\u7edf\u4e2d\u53c8\u65b0\u589e\u4e00\u4e2a\u8fdb\u7a0bp3226\uff0c\u5bf9\u4e8e\u6b64\u65f6\u7684\u7236\u8fdb\u7a0b\uff0cp2043->p3224\uff08\u5f53\u524d\u8fdb\u7a0b\uff09->p3226\uff08\u88ab\u521b\u5efa\u7684\u5b50\u8fdb\u7a0b\uff09\u3002
          \n\u5bf9\u4e8e\u5b50\u8fdb\u7a0bp3225\uff0c\u6267\u884c\u5b8c\u7b2c\u4e00\u6b21\u5faa\u73af\u540e\uff0ci=1\uff0c\u63a5\u7740\u6267\u884cfork\uff0c\u7cfb\u7edf\u4e2d\u65b0\u589e\u4e00\u4e2a\u8fdb\u7a0bp3227\uff0c\u5bf9\u4e8e\u6b64\u8fdb\u7a0b\uff0cp3224->p3225\uff08\u5f53\u524d\u8fdb\u7a0b\uff09->p3227\uff08\u88ab\u521b\u5efa\u7684\u5b50\u8fdb\u7a0b\uff09\u3002\u4ece\u8f93\u51fa\u53ef\u4ee5\u770b\u5230p3225\u539f\u6765\u662fp3224\u7684\u5b50\u8fdb\u7a0b\uff0c\u73b0\u5728\u53d8\u6210p3227\u7684\u7236\u8fdb\u7a0b\u3002\u7236\u5b50\u662f\u76f8\u5bf9\u7684\uff0c\u8fd9\u4e2a\u5927\u5bb6\u5e94\u8be5\u5bb9\u6613\u7406\u89e3\u3002\u53ea\u8981\u5f53\u524d\u8fdb\u7a0b\u6267\u884c\u4e86fork\uff0c\u8be5\u8fdb\u7a0b\u5c31\u53d8\u6210\u4e86\u7236\u8fdb\u7a0b\u4e86\uff0c\u5c31\u6253\u5370\u51fa\u4e86parent\u3002
          \n\u6240\u4ee5\u6253\u5370\u51fa\u7ed3\u679c\u662f\uff1a
          \n1 parent 2043 3224 3226
          \n1 parent 3224 3225 3227
          \n\u7b2c\u4e09\u6b65\uff1a\u7b2c\u4e8c\u6b65\u521b\u5efa\u4e86\u4e24\u4e2a\u8fdb\u7a0bp3226\uff0cp3227\uff0c\u8fd9\u4e24\u4e2a\u8fdb\u7a0b\u6267\u884c\u5b8cprintf\u51fd\u6570\u540e\u5c31\u7ed3\u675f\u4e86\uff0c\u56e0\u4e3a\u8fd9\u4e24\u4e2a\u8fdb\u7a0b\u65e0\u6cd5\u8fdb\u5165\u7b2c\u4e09\u6b21\u5faa\u73af\uff0c\u65e0\u6cd5fork\uff0c\u8be5\u6267\u884creturn 0;\u4e86\uff0c\u5176\u4ed6\u8fdb\u7a0b\u4e5f\u662f\u5982\u6b64\u3002
          \n\u4ee5\u4e0b\u662fp3226\uff0cp3227\u6253\u5370\u51fa\u7684\u7ed3\u679c\uff1a
          \n1 child\u00a0\u00a0\u00a0\u00a0 1 3227\u00a0\u00a0\u00a0 0
          \n1 child\u00a0\u00a0\u00a0\u00a0 1 3226\u00a0\u00a0\u00a0 0
          \n\u7ec6\u5fc3\u7684\u8bfb\u8005\u53ef\u80fd\u6ce8\u610f\u5230p3226\uff0cp3227\u7684\u7236\u8fdb\u7a0b\u96be\u9053\u4e0d\u8be5\u662fp3224\u548cp3225\u5417\uff0c\u600e\u4e48\u4f1a\u662f1\u5462\uff1f\u8fd9\u91cc\u5f97\u8bb2\u5230\u8fdb\u7a0b\u7684\u521b\u5efa\u548c\u6b7b\u4ea1\u7684\u8fc7\u7a0b\uff0c\u5728p3224\u548cp3225\u6267\u884c\u5b8c\u7b2c\u4e8c\u4e2a\u5faa\u73af\u540e\uff0cmain\u51fd\u6570\u5c31\u8be5\u9000\u51fa\u4e86\uff0c\u4e5f\u5373\u8fdb\u7a0b\u8be5\u6b7b\u4ea1\u4e86\uff0c\u56e0\u4e3a\u5b83\u5df2\u7ecf\u505a\u5b8c\u6240\u6709\u4e8b\u60c5\u4e86\u3002p3224\u548cp3225\u6b7b\u4ea1\u540e\uff0cp3226\uff0cp3227\u5c31\u6ca1\u6709\u7236\u8fdb\u7a0b\u4e86\uff0c\u8fd9\u5728\u64cd\u4f5c\u7cfb\u7edf\u662f\u4e0d\u88ab\u5141\u8bb8\u7684\uff0c\u6240\u4ee5p3226\uff0cp3227\u7684\u7236\u8fdb\u7a0b\u5c31\u88ab\u7f6e\u4e3ap1\u4e86\uff0cp1\u662f\u6c38\u8fdc\u4e0d\u4f1a\u6b7b\u4ea1\u7684\uff0c\u81f3\u4e8e\u4e3a\u4ec0\u4e48\uff0c\u8fd9\u91cc\u5148\u4e0d\u4ecb\u7ecd\uff0c\u7559\u5230\u201c\u4e09\u3001fork\u9ad8\u9636\u77e5\u8bc6\u201d\u8bb2\u3002
          \n\u603b\u7ed3\u4e00\u4e0b\uff0c\u8fd9\u4e2a\u7a0b\u5e8f\u6267\u884c\u7684\u6d41\u7a0b\u5982\u4e0b\uff1a<\/p>\n

          \u8fd9\u4e2a\u7a0b\u5e8f\u6700\u7ec8\u4ea7\u751f\u4e863\u4e2a\u5b50\u8fdb\u7a0b\uff0c\u6267\u884c\u8fc76\u6b21printf\uff08\uff09\u51fd\u6570\u3002
          \n\u6211\u4eec\u518d\u6765\u770b\u4e00\u4efd\u4ee3\u7801\uff1a<\/p>\n

          [cpp]<\/strong>\u00a0view plain<\/a>\u00a0copy<\/a><\/span><\/p>\n

            \n
          1. \/*<\/li>\n
          2. \u00a0*\u00a0\u00a0fork_test.c<\/li>\n
          3. \u00a0*\u00a0\u00a0version\u00a03<\/li>\n
          4. \u00a0*\u00a0\u00a0Created\u00a0on:\u00a02010-5-29<\/li>\n
          5. \u00a0*\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0Author:\u00a0wangth<\/li>\n
          6. \u00a0*\/<\/li>\n
          7. #include\u00a0<unistd.h><\/li>\n
          8. #include\u00a0<stdio.h><\/li>\n
          9. int<\/b>\u00a0main(void<\/b>)<\/li>\n
          10. {<\/li>\n
          11. \u00a0\u00a0\u00a0int<\/b>\u00a0i=0;<\/li>\n
          12. \u00a0\u00a0\u00a0for<\/b>(i=0;i<3;i++){<\/li>\n
          13. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0pid_t\u00a0fpid=fork();<\/li>\n
          14. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0if<\/b>(fpid==0)<\/li>\n
          15. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0printf(“son\/n”);<\/li>\n
          16. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0else<\/b><\/li>\n
          17. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0printf(“father\/n”);<\/li>\n
          18. \u00a0\u00a0\u00a0}<\/li>\n
          19. \u00a0\u00a0\u00a0return<\/b>\u00a00;<\/li>\n
          20. <\/li>\n
          21. }<\/li>\n<\/ol>\n

            \u5b83\u7684\u6267\u884c\u7ed3\u679c\u662f\uff1a
            \nfather
            \nson
            \nfather
            \nfather
            \nfather
            \nfather
            \nson
            \nson
            \nfather
            \nson
            \nson
            \nson
            \nfather
            \nson
            \n\u8fd9\u91cc\u5c31\u4e0d\u505a\u8be6\u7ec6\u89e3\u91ca\u4e86\uff0c\u53ea\u505a\u4e00\u4e2a\u5927\u6982\u7684\u5206\u6790\u3002
            \nfor\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 i=0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 1\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 2
            \nfather\u00a0\u00a0\u00a0\u00a0 father\u00a0\u00a0\u00a0\u00a0 father
            \nson
            \nson\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 father
            \nson
            \nson\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 father\u00a0\u00a0\u00a0\u00a0 father
            \nson
            \nson\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 father
            \nson
            \n\u5176\u4e2d\u6bcf\u4e00\u884c\u5206\u522b\u4ee3\u8868\u4e00\u4e2a\u8fdb\u7a0b\u7684\u8fd0\u884c\u6253\u5370\u7ed3\u679c\u3002
            \n\u603b\u7ed3\u4e00\u4e0b\u89c4\u5f8b\uff0c\u5bf9\u4e8e\u8fd9\u79cdN\u6b21\u5faa\u73af\u7684\u60c5\u51b5\uff0c\u6267\u884cprintf\u51fd\u6570\u7684\u6b21\u6570\u4e3a2*\uff081+2+4+\u2026\u2026+2N-1<\/sup>\uff09\u6b21\uff0c\u521b\u5efa\u7684\u5b50\u8fdb\u7a0b\u6570\u4e3a1+2+4+\u2026\u2026+2N-1<\/sup>\u4e2a\u3002(\u611f\u8c22gao_jiawei\u7f51\u53cb\u6307\u51fa\u7684\u9519\u8bef\uff0c\u539f\u672c\u6211\u7684\u7ed3\u8bba\u662f\u201c\u6267\u884cprintf\u51fd\u6570\u7684\u6b21\u6570\u4e3a2*\uff081+2+4+\u2026\u2026+2N<\/sup>\uff09\u6b21\uff0c\u521b\u5efa\u7684\u5b50\u8fdb\u7a0b\u6570\u4e3a1+2+4+\u2026\u2026+2N\u00a0<\/sup>\u201d\uff0c\u8fd9\u662f\u9519\u7684)<\/strong>
            \n\u7f51\u4e0a\u6709\u4eba\u8bf4N\u6b21\u5faa\u73af\u4ea7\u751f2*\uff081+2+4+\u2026\u2026+2N<\/sup>\uff09\u4e2a\u8fdb\u7a0b\uff0c\u8fd9\u4e2a\u8bf4\u6cd5\u662f\u4e0d\u5bf9\u7684\uff0c\u5e0c\u671b\u5927\u5bb6\u9700\u8981\u6ce8\u610f\u3002<\/p>\n

            \u6570\u5b66\u63a8\u7406\u89c1http:\/\/202.117.3.13\/wordpress\/?p=81<\/a>\uff08\u8be5\u535a\u6587\u7684\u6700\u540e\uff09\u3002
            \n\u540c\u65f6\uff0c\u5927\u5bb6\u5982\u679c\u60f3\u6d4b\u4e00\u4e0b\u4e00\u4e2a\u7a0b\u5e8f\u4e2d\u5230\u5e95\u521b\u5efa\u4e86\u51e0\u4e2a\u5b50\u8fdb\u7a0b\uff0c\u6700\u597d\u7684\u65b9\u6cd5\u5c31\u662f\u8c03\u7528printf\u51fd\u6570\u6253\u5370\u8be5\u8fdb\u7a0b\u7684pid\uff0c\u4e5f\u5373\u8c03\u7528printf(“%d\/n”,getpid());\u6216\u8005\u901a\u8fc7printf(“+\/n”);\u6765\u5224\u65ad\u4ea7\u751f\u4e86\u51e0\u4e2a\u8fdb\u7a0b\u3002\u6709\u4eba\u60f3\u901a\u8fc7\u8c03\u7528printf(“+”);\u6765\u7edf\u8ba1\u521b\u5efa\u4e86\u51e0\u4e2a\u8fdb\u7a0b\uff0c\u8fd9\u662f\u4e0d\u59a5\u5f53\u7684\u3002\u5177\u4f53\u539f\u56e0\u6211\u6765\u5206\u6790\u3002
            \n\u8001\u89c4\u77e9\uff0c\u5927\u5bb6\u770b\u4e00\u4e0b\u4e0b\u9762\u7684\u4ee3\u7801\uff1a<\/p>\n

            [cpp]<\/strong>\u00a0view plain<\/a>\u00a0copy<\/a><\/span><\/p>\n

              \n
            1. \/*<\/li>\n
            2. \u00a0*\u00a0\u00a0fork_test.c<\/li>\n
            3. \u00a0*\u00a0\u00a0version\u00a04<\/li>\n
            4. \u00a0*\u00a0\u00a0Created\u00a0on:\u00a02010-5-29<\/li>\n
            5. \u00a0*\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0Author:\u00a0wangth<\/li>\n
            6. \u00a0*\/<\/li>\n
            7. #include\u00a0<unistd.h><\/li>\n
            8. #include\u00a0<stdio.h><\/li>\n
            9. int<\/b>\u00a0main()\u00a0{<\/li>\n
            10. \u00a0\u00a0\u00a0\u00a0pid_t\u00a0fpid;\/\/fpid\u8868\u793afork\u51fd\u6570\u8fd4\u56de\u7684\u503c<\/li>\n
            11. \u00a0\u00a0\u00a0\u00a0\/\/printf(“fork!”);<\/li>\n
            12. \u00a0\u00a0\u00a0\u00a0printf(“fork!\/n”);<\/li>\n
            13. \u00a0\u00a0\u00a0\u00a0fpid\u00a0=\u00a0fork();<\/li>\n
            14. \u00a0\u00a0\u00a0\u00a0if<\/b>\u00a0(fpid\u00a0<\u00a00)<\/li>\n
            15. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0printf(“error\u00a0in\u00a0fork!”);<\/li>\n
            16. \u00a0\u00a0\u00a0\u00a0else<\/b>\u00a0if<\/b>\u00a0(fpid\u00a0==\u00a00)<\/li>\n
            17. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0printf(“I\u00a0am\u00a0the\u00a0child\u00a0process,\u00a0my\u00a0process\u00a0id\u00a0is\u00a0%d\/n”,\u00a0getpid());<\/li>\n
            18. \u00a0\u00a0\u00a0\u00a0else<\/b><\/li>\n
            19. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0printf(“I\u00a0am\u00a0the\u00a0parent\u00a0process,\u00a0my\u00a0process\u00a0id\u00a0is\u00a0%d\/n”,\u00a0getpid());<\/li>\n
            20. \u00a0\u00a0\u00a0\u00a0return<\/b>\u00a00;<\/li>\n
            21. }<\/li>\n<\/ol>\n

              \u6267\u884c\u7ed3\u679c\u5982\u4e0b\uff1a
              \nfork!
              \nI am the parent process, my process id is 3361
              \nI am the child process, my process id is 3362
              \n\u5982\u679c\u628a\u8bed\u53e5printf(“fork!\/n”);\u6ce8\u91ca\u6389\uff0c\u6267\u884cprintf(“fork!”);
              \n\u5219\u65b0\u7684\u7a0b\u5e8f\u7684\u6267\u884c\u7ed3\u679c\u662f\uff1a
              \nfork!I am the parent process, my process id is 3298
              \nfork!I am the child process, my process id is 3299
              \n\u7a0b\u5e8f\u7684\u552f\u4e00\u7684\u533a\u522b\u5c31\u5728\u4e8e\u4e00\u4e2a\/n\u56de\u8f66\u7b26\u53f7\uff0c\u4e3a\u4ec0\u4e48\u7ed3\u679c\u4f1a\u76f8\u5dee\u8fd9\u4e48\u5927\u5462\uff1f
              \n\u8fd9\u5c31\u8ddfprintf\u7684\u7f13\u51b2\u673a\u5236\u6709\u5173\u4e86\uff0cprintf\u67d0\u4e9b\u5185\u5bb9\u65f6\uff0c\u64cd\u4f5c\u7cfb\u7edf\u4ec5\u4ec5\u662f\u628a\u8be5\u5185\u5bb9\u653e\u5230\u4e86stdout\u7684\u7f13\u51b2\u961f\u5217\u91cc\u4e86,\u5e76\u6ca1\u6709\u5b9e\u9645\u7684\u5199\u5230\u5c4f\u5e55\u4e0a\u3002\u4f46\u662f,\u53ea\u8981\u770b\u5230\u6709\/n \u5219\u4f1a\u7acb\u5373\u5237\u65b0stdout,\u56e0\u6b64\u5c31\u9a6c\u4e0a\u80fd\u591f\u6253\u5370\u4e86\u3002
              \n\u8fd0\u884c\u4e86printf(“fork!”)\u540e,\u201cfork!\u201d\u4ec5\u4ec5\u88ab\u653e\u5230\u4e86\u7f13\u51b2\u91cc,\u7a0b\u5e8f\u8fd0\u884c\u5230fork\u65f6\u7f13\u51b2\u91cc\u9762\u7684\u201cfork!\u201d\u00a0 \u88ab\u5b50\u8fdb\u7a0b\u590d\u5236\u8fc7\u53bb\u4e86\u3002\u56e0\u6b64\u5728\u5b50\u8fdb\u7a0b\u5ea6stdout\u7f13\u51b2\u91cc\u9762\u5c31\u4e5f\u6709\u4e86fork! \u3002\u6240\u4ee5,\u4f60\u6700\u7ec8\u770b\u5230\u7684\u4f1a\u662ffork!\u00a0 \u88abprintf\u4e862\u6b21\uff01\uff01\uff01\uff01
              \n\u800c\u8fd0\u884cprintf(“fork! \/n”)\u540e,\u201cfork!\u201d\u88ab\u7acb\u5373\u6253\u5370\u5230\u4e86\u5c4f\u5e55\u4e0a,\u4e4b\u540efork\u5230\u7684\u5b50\u8fdb\u7a0b\u91cc\u7684stdout\u7f13\u51b2\u91cc\u4e0d\u4f1a\u6709fork! \u5185\u5bb9\u3002\u56e0\u6b64\u4f60\u770b\u5230\u7684\u7ed3\u679c\u4f1a\u662ffork! \u88abprintf\u4e861\u6b21\uff01\uff01\uff01\uff01
              \n\u6240\u4ee5\u8bf4printf(“+”);\u4e0d\u80fd\u6b63\u786e\u5730\u53cd\u5e94\u8fdb\u7a0b\u7684\u6570\u91cf\u3002
              \n\u5927\u5bb6\u770b\u4e86\u8fd9\u4e48\u591a\u53ef\u80fd\u6709\u70b9\u75b2\u5026\u5427\uff0c\u4e0d\u8fc7\u6211\u8fd8\u5f97\u8d34\u6700\u540e\u4e00\u4efd\u4ee3\u7801\u6765\u8fdb\u4e00\u6b65\u5206\u6790fork\u51fd\u6570\u3002<\/p>\n

              [cpp]<\/strong>\u00a0view plain<\/a>\u00a0copy<\/a><\/span><\/p>\n

                \n
              1. #include\u00a0<stdio.h><\/li>\n
              2. #include\u00a0<unistd.h><\/li>\n
              3. int<\/b>\u00a0main(int<\/b>\u00a0argc,\u00a0char<\/b>*\u00a0argv[])<\/li>\n
              4. {<\/li>\n
              5. \u00a0\u00a0\u00a0fork();<\/li>\n
              6. \u00a0\u00a0\u00a0fork()\u00a0&&\u00a0fork()\u00a0||\u00a0fork();<\/li>\n
              7. \u00a0\u00a0\u00a0fork();<\/li>\n
              8. \u00a0\u00a0\u00a0return<\/b>\u00a00;<\/li>\n
              9. }<\/li>\n<\/ol>\n

                \u95ee\u9898\u662f\u4e0d\u7b97main\u8fd9\u4e2a\u8fdb\u7a0b\u81ea\u8eab\uff0c\u7a0b\u5e8f\u5230\u5e95\u521b\u5efa\u4e86\u591a\u5c11\u4e2a\u8fdb\u7a0b\u3002
                \n\u4e3a\u4e86\u89e3\u7b54\u8fd9\u4e2a\u95ee\u9898\uff0c\u6211\u4eec\u5148\u505a\u4e00\u4e0b\u5f0a\uff0c\u5148\u7528\u7a0b\u5e8f\u9a8c\u8bc1\u4e00\u4e0b\uff0c\u5230\u6b64\u6709\u591a\u5c11\u4e2a\u8fdb\u7a0b\u3002<\/p>\n

                [c-sharp]<\/strong>\u00a0view plain<\/a>\u00a0copy<\/a><\/span><\/p>\n

                  \n
                1. #include\u00a0<stdio.h><\/li>\n
                2. int<\/b>\u00a0main(int<\/b>\u00a0argc,\u00a0char<\/b>*\u00a0argv[])<\/li>\n
                3. {<\/li>\n
                4. \u00a0\u00a0\u00a0fork();<\/li>\n
                5. \u00a0\u00a0\u00a0fork()\u00a0&&\u00a0fork()\u00a0||\u00a0fork();<\/li>\n
                6. \u00a0\u00a0\u00a0fork();<\/li>\n
                7. \u00a0\u00a0\u00a0printf(“+\/n”);<\/li>\n
                8. }<\/li>\n<\/ol>\n

                  \u7b54\u6848\u662f\u603b\u517120\u4e2a\u8fdb\u7a0b\uff0c\u9664\u53bbmain\u8fdb\u7a0b\uff0c\u8fd8\u670919\u4e2a\u8fdb\u7a0b\u3002
                  \n\u6211\u4eec\u518d\u6765\u4ed4\u7ec6\u5206\u6790\u4e00\u4e0b\uff0c\u4e3a\u4ec0\u4e48\u662f\u8fd8\u670919\u4e2a\u8fdb\u7a0b\u3002
                  \n\u7b2c\u4e00\u4e2afork\u548c\u6700\u540e\u4e00\u4e2afork\u80af\u5b9a\u662f\u4f1a\u6267\u884c\u7684\u3002
                  \n\u4e3b\u8981\u5728\u4e2d\u95f43\u4e2afork\u4e0a\uff0c\u53ef\u4ee5\u753b\u4e00\u4e2a\u56fe\u8fdb\u884c\u63cf\u8ff0\u3002
                  \n\u8fd9\u91cc\u5c31\u9700\u8981\u6ce8\u610f&&\u548c||\u8fd0\u7b97\u7b26\u3002
                  \nA&&B\uff0c\u5982\u679cA=0\uff0c\u5c31\u6ca1\u6709\u5fc5\u8981\u7ee7\u7eed\u6267\u884c&&B\u4e86\uff1bA\u975e0\uff0c\u5c31\u9700\u8981\u7ee7\u7eed\u6267\u884c&&B\u3002
                  \nA||B\uff0c\u5982\u679cA\u975e0\uff0c\u5c31\u6ca1\u6709\u5fc5\u8981\u7ee7\u7eed\u6267\u884c||B\u4e86\uff0cA=0\uff0c\u5c31\u9700\u8981\u7ee7\u7eed\u6267\u884c||B\u3002
                  \nfork()\u5bf9\u4e8e\u7236\u8fdb\u7a0b\u548c\u5b50\u8fdb\u7a0b\u7684\u8fd4\u56de\u503c\u662f\u4e0d\u540c\u7684\uff0c\u6309\u7167\u4e0a\u9762\u7684A&&B\u548cA||B\u7684\u5206\u652f\u8fdb\u884c\u753b\u56fe\uff0c\u53ef\u4ee5\u5f97\u51fa5\u4e2a\u5206\u652f\u3002<\/p>\n

                   <\/p>\n

                  \u52a0\u4e0a\u524d\u9762\u7684fork\u548c\u6700\u540e\u7684fork\uff0c\u603b\u51714*5=20\u4e2a\u8fdb\u7a0b\uff0c\u9664\u53bbmain\u4e3b\u8fdb\u7a0b\uff0c\u5c31\u662f19\u4e2a\u8fdb\u7a0b\u4e86\u3002<\/p>\n

                  \u4e09\u3001fork\u9ad8\u9636\u77e5\u8bc6<\/strong><\/p>\n

                  \u8fd9\u4e00\u5757\u6211\u4e3b\u8981\u5c31fork\u51fd\u6570\u8bb2\u4e00\u4e0b\u64cd\u4f5c\u7cfb\u7edf\u8fdb\u7a0b\u7684\u521b\u5efa\u3001\u6b7b\u4ea1\u548c\u8c03\u5ea6\u7b49\u3002\u56e0\u4e3a\u65f6\u95f4\u548c\u7cbe\u529b\u9650\u5236\uff0c\u6211\u5148\u5199\u5230\u8fd9\u91cc\uff0c\u4e0b\u6b21\u627e\u4e2a\u65f6\u95f4\u6211\u4e89\u53d6\u628a\u5269\u4e0b\u7684\u5185\u5bb9\u8865\u9f50\u3002<\/p>\n

                   <\/p>\n

                   <\/p>\n

                   <\/p>\n

                  \u53c2\u8003\u8d44\u6599\uff1a<\/strong><\/p>\n

                   <\/p>\n

                  http:\/\/blog.csdn.net\/dog_in_yellow\/archive\/2008\/01\/13\/2041079.aspx<\/a><\/p>\n

                  http:\/\/blog.chinaunix.net\/u1\/53053\/showart_425189.html<\/a><\/p>\n

                  http:\/\/blog.csdn.net\/saturnbj\/archive\/2009\/06\/19\/4282639.aspx<\/a><\/p>\n

                  http:\/\/www.cppblog.com\/zhangxu\/archive\/2007\/12\/02\/37640.html<\/a><\/p>\n

                  http:\/\/www.qqread.com\/linux\/2010\/03\/y491043.html<\/a><\/p>\n

                  http:\/\/www.yuanma.org\/data\/2009\/1103\/article_3998.htm<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

                  \u00a0\u6807\u7b7e\uff1a\u00a0linux2010\u5b58\u50a8 201<\/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":[118],"class_list":["post-580","post","type-post","status-publish","format-standard","hentry","tag-02-"],"_links":{"self":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/580","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=580"}],"version-history":[{"count":0,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/580\/revisions"}],"wp:attachment":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/media?parent=580"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/categories?post=580"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/tags?post=580"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}