{"id":496,"date":"2017-09-29T17:38:41","date_gmt":"2017-09-29T09:38:41","guid":{"rendered":"https:\/\/i007.cc\/wordpress\/?p=496"},"modified":"2019-06-25T19:24:46","modified_gmt":"2019-06-25T11:24:46","slug":"%e4%b8%80%e4%b8%aa%e8%af%af%e7%94%a8snprintf%e7%9a%84bug%e5%88%86%e6%9e%90","status":"publish","type":"post","link":"https:\/\/i007.cc\/wordpress\/archives\/496","title":{"rendered":"\u4e00\u4e2a\u8bef\u7528snprintf\u7684bug\u5206\u6790"},"content":{"rendered":"
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\u7ed3\u8bba\uff1aint64_t \u5e94\u8be5\u4f7f\u7528%lld\u8f93\u51fa<\/strong><\/div>\n<\/div>\n
\u00a0<\/strong><\/em><\/div>\n
\n

\u76ee\u5f55(?)<\/a>[+]<\/a><\/p>\n<\/div>\n

<\/div>\n
\n

\u00a0 \u00a0 \u00a0 \u00a0 \u00a0\u8f6c\u8f7d\u5730\u5740\uff1a\u00a0http:\/\/blog.csdn.net\/wuchun\/article\/details\/38455609<\/p>\n

 <\/p>\n

<\/a>\u524d\u8a00<\/h1>\n

snprintf\u51fd\u6570\u7684\u529f\u80fd\u662f\u683c\u5f0f\u5316\u8f93\u51fa\u5230\u5b57\u7b26\u4e32\u4e2d\uff0c\u51fd\u6570\u539f\u578b\u4e3a\uff1a<\/p>\n

int snprintf(char *str, size_t size, const char *fomat, …)<\/p>\n

\u6b63\u5e38\u6765\u8bf4\uff0c\u53ea\u8981\u4f1a\u7528printf\u51fd\u6570\u5199\u8f93\u51fa\u8bed\u53e5\uff0c\u5e94\u8be5\u90fd\u80fd\u4f1a\u7528\u8be5\u51fd\u6570\u3002\u4f46\u662f\uff0c\u7a0d\u6709\u4e0d\u7559\u795e\uff0c\u5f88\u53ef\u80fd\u8e29\u5230\u5176\u4e2d\u7684\u5751\u3002\u73b0\u5c06\u524d\u6bb5\u65f6\u95f4\u9047\u5230\u7684\u4e00\u4e2a\u95ee\u9898\u8fdb\u884c\u7b80\u5355\u5730\u5206\u6790\u3002<\/p>\n

<\/a><\/a>\u95ee\u9898<\/h1>\n

\u4ee5\u4e0b\u662f\u62bd\u53d6\u51fa\u6765\u7684\u95ee\u9898\u4ee3\u7801\u6bb5\uff1a<\/p>\n

\n
\n
\n

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

<\/embed><\/div>\n
<\/div>\n<\/div>\n<\/div>\n
    \n
  1. #include\u00a0<stdio.h><\/span><\/li>\n
  2. #include\u00a0<iostream><\/span><\/li>\n
  3. <\/li>\n
  4. class<\/span>\u00a0A<\/li>\n
  5. {<\/li>\n
  6. \u00a0\u00a0\u00a0\u00a0public<\/span>:<\/li>\n
  7. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0int64_t\u00a0b;<\/li>\n
  8. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0char<\/span>*\u00a0pstr;<\/li>\n
  9. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0int<\/span>\u00a0a;<\/li>\n
  10. <\/li>\n
  11. };<\/li>\n
  12. <\/li>\n
  13. int<\/span>\u00a0main()<\/li>\n
  14. {<\/li>\n
  15. \u00a0\u00a0\u00a0\u00a0char<\/span>\u00a0source[128]\u00a0=\u00a0“hello\u00a0world”<\/span>;<\/li>\n
  16. \u00a0\u00a0\u00a0\u00a0char<\/span>\u00a0tstr[128]\u00a0=\u00a0“\\0”<\/span>;<\/li>\n
  17. \u00a0\u00a0\u00a0\u00a0A\u00a0a;<\/li>\n
  18. \u00a0\u00a0\u00a0\u00a0a.a=0x0001;<\/li>\n
  19. \u00a0\u00a0\u00a0\u00a0a.b=0x00030004;<\/li>\n
  20. \u00a0\u00a0\u00a0\u00a0a.pstr\u00a0=\u00a0source;<\/li>\n
  21. <\/li>\n
  22. \u00a0\u00a0\u00a0\u00a0snprintf(tstr,\u00a0sizeof<\/span>(tstr),\u00a0“b=%ld,str=%s,a=%d\\n”<\/span>,\u00a0a.b,\u00a0a.pstr,\u00a0a.a);<\/li>\n
  23. \u00a0\u00a0\u00a0\u00a0printf(“%s”<\/span>,tstr);<\/li>\n
  24. \u00a0\u00a0\u00a0\u00a0\/\/printf(“%s\\nsource\u00a0address:%ld\\n”,tstr,\u00a0source);\u00a0\/\/\u67e5\u627e\u95ee\u9898\u65f6\u589e\u52a0<\/span><\/li>\n
  25. <\/li>\n
  26. \u00a0\u00a0\u00a0\u00a0return<\/span>\u00a00;<\/li>\n
  27. }<\/li>\n<\/ol>\n<\/div>\n

    \u5982\u4e0a\u6240\u793a\uff0c\u529f\u80fd\u6bd4\u8f83\u7b80\u5355\uff0c\u5c31\u662f\u4f7f\u7528snprintf\u51fd\u6570\u5c06\u7c7bA\u4e2d\u7684\u53d8\u91cf\u503c\u683c\u5f0f\u5316\u8f93\u51fa\u5230tstr\u5b57\u7b26\u4e32\u4e2d\u3002\u9996\u5148\u5c06\u5176\u7f16\u8bd1\u621064\u4f4d\u7a0b\u5e8f\uff1a(\u6ce8\uff1a\u672c\u6587\u4e2d\u6240\u7528gcc\u7248\u672c\u4e3a4.1.2)<\/p>\n

    g++ -g -m64 -o tsn tsn.cpp<\/p>\n

    \u8fd0\u884ctsn\uff0c\u7ed3\u679c\u4e3a\uff1a<\/p>\n

    b=196612,str=hello world,a=1<\/p>\n

    \u4e00\u5207\u6b63\u5e38\u3002<\/p>\n

    \u4f46\u5f53\u7528g++ -g -m32 -o tsn tsn.cpp\u5c06\u5176\u7f16\u8bd1\u4e3a32\u4f4d\u7a0b\u5e8f\u540e\uff0c\u95ee\u9898\u51fa\u73b0\u4e86\uff0c\u8fd0\u884ctsn\u540e\uff0c\u7ed3\u679c\u4e3a\uff1a<\/p>\n

    b=196612,str=(null),a=-2270288<\/p>\n

    \u4ece\u7ed3\u679c\u6765\u770b\uff0c\u5e94\u8be5\u662fa.pstr\u548ca.a\u5f15\u7528\u7684\u5730\u5740\u51fa\u4e86\u95ee\u9898\uff0c\u4e8e\u662f\u5728\u4ee3\u7801\u4e2d\u589e\u52a0\u4e86\u4e00\u884c\u8bed\u53e5\uff0c\u6253\u5370a.pstr\u6240\u6307\u5411\u7684source\u5730\u5740\uff0c\u4fee\u6539\u540e\uff0c\u7f16\u8bd1\u621032\u4f4d\uff0c\u8fd0\u884c\u7ed3\u679c\u5982\u4e0b\uff1a<\/p>\n

    b=196612,str=(null),a=-2270288<\/p>\n

    source address:-2270288<\/p>\n

    \u4ece\u7ed3\u679c\u53d1\u73b0a\u7684\u503c\u53d8\u6210\u4e86source\u7684\u5730\u5740\uff0c\u8fd9\u65f6\u7a81\u7136\u610f\u8bc6\u5230snprintf\u662f\u4e00\u4e2a\u53ef\u53d8\u53c2\u6570\u7684\u51fd\u6570\uff0c\u5176\u5e94\u8be5\u4e5f\u662f\u4f7f\u7528va_arg\u6765\u8bfb\u53d6\u5806\u6808\u4e2d\u53ef\u53d8\u53c2\u6570\uff0c\u800cva_arg\u6765\u8bfb\u53d6\u53c2\u6570\u65f6\uff0c\u662f\u6309\u7167\u6307\u5b9a\u5927\u5c0f\u6765\u8bbf\u95ee\uff0c\u5f88\u53ef\u80fd\u662f\u6307\u5b9a\u7684\u8bbf\u95ee\u5927\u5c0f\u51fa\u73b0\u4e86\u95ee\u9898\u6240\u5bfc\u81f4(\u6ce8\uff1asnprintf\u51fd\u6570\u5185\u90e8\u662f\u5426\u901a\u8fc7va_arg\u6765\u5b9e\u73b0\uff0c\u672c\u4eba\u5e76\u672a\u8fdb\u884c\u7814\u7a76\uff0c\u53ea\u662f\u5728\u627e\u95ee\u9898\u65f6\u731c\u6d4b\u5176\u53ef\u80fd\u6027)\uff0c\u679c\u7136\uff0c\u53d1\u73b0\u5728A\u4e2d\u7684\u53d8\u91cfb\u5b9a\u4e49\u7684\u662fint64_t\uff0c\u800c\u5728\u683c\u5f0f\u5316\u8f93\u51fa\u65f6\u7528\u7684\u5374\u662f%ld\uff0c\u6b63\u786e\u5730\u5e94\u5f53\u4f7f\u7528%lld\u3002<\/p>\n

    <\/a><\/a>\u5206\u6790<\/h1>\n

    \u95ee\u9898\u770b\u4f3c\u627e\u5230\u4e86\uff0c\u800c\u4e14\u4e5f\u89e3\u51b3\u4e86\uff0c\u4f46\u662f\u4e3a\u4ec0\u4e48\u5c06\u5176\u7f16\u8bd164\u4f4d\u65f6\u4e0d\u4f1a\u51fa\u73b0\u95ee\u9898\u5462\uff1f\u4e8e\u662f\u51b3\u5b9a\u67e5\u770b\u4e8c\u8005\u7684\u6c47\u7f16\u6307\u4ee4\u5dee\u522b\u5728\u54ea\u91cc\u3002<\/p>\n

    \u9996\u5148\uff0c\u4f7f\u7528objdump -S tsn\uff0c\u751f\u621064\u4f4d\u7a0b\u5e8f\u6c47\u7f16\u6307\u4ee4\uff0c\u53bb\u6389\u4e0d\u76f8\u5173\u5185\u5bb9\u540e\uff0c\u5982\u4e0b\u6240\u793a<\/p>\n

    \n
    \n
    \n

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

    <\/embed><\/div>\n
    <\/div>\n<\/div>\n<\/div>\n
      \n
    1. 4007f3:\u00a0c7\u00a045\u00a0f0\u00a001\u00a000\u00a000\u00a000\u00a0\u00a0\u00a0\u00a0movl\u00a0\u00a0\u00a0$0x1,0xfffffffffffffff0(%rbp)<\/li>\n
    2. 4007fa:\u00a048\u00a0c7\u00a045\u00a0e0\u00a004\u00a000\u00a003\u00a0\u00a0\u00a0\u00a0movq\u00a0\u00a0\u00a0$0x30004,0xffffffffffffffe0(%rbp)<\/li>\n
    3. 400801:\u00a000<\/li>\n
    4. 400802:\u00a048\u00a08d\u00a085\u00a060\u00a0ff\u00a0ff\u00a0ff\u00a0\u00a0\u00a0\u00a0lea\u00a0\u00a0\u00a0\u00a00xffffffffffffff60(%rbp),%rax<\/li>\n
    5. 400809:\u00a048\u00a089\u00a045\u00a0e8\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0mov\u00a0\u00a0\u00a0\u00a0%rax,0xffffffffffffffe8(%rbp)<\/li>\n
    6. 40080d:\u00a08b\u00a045\u00a0f0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0mov\u00a0\u00a0\u00a0\u00a00xfffffffffffffff0(%rbp),%eax<\/li>\n
    7. 400810:\u00a048\u00a08b\u00a055\u00a0e8\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0mov\u00a0\u00a0\u00a0\u00a00xffffffffffffffe8(%rbp),%rdx<\/li>\n
    8. 400814:\u00a048\u00a08b\u00a04d\u00a0e0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0mov\u00a0\u00a0\u00a0\u00a00xffffffffffffffe0(%rbp),%rcx<\/li>\n
    9. 400818:\u00a048\u00a08d\u00a0bd\u00a0e0\u00a0fe\u00a0ff\u00a0ff\u00a0\u00a0\u00a0\u00a0lea\u00a0\u00a0\u00a0\u00a00xfffffffffffffee0(%rbp),%rdi<\/li>\n
    10. 40081f:\u00a041\u00a089\u00a0c1\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0mov\u00a0\u00a0\u00a0\u00a0%eax,%r9d<\/li>\n
    11. 400822:\u00a049\u00a089\u00a0d0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0mov\u00a0\u00a0\u00a0\u00a0%rdx,%r8<\/li>\n
    12. 400825:\u00a0ba\u00a058\u00a009\u00a040\u00a000\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0mov\u00a0\u00a0\u00a0\u00a0$0x400958,%edx<\/li>\n
    13. 40082a:\u00a0be\u00a080\u00a000\u00a000\u00a000\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0mov\u00a0\u00a0\u00a0\u00a0$0x80,%esi<\/li>\n
    14. 40082f:\u00a0b8\u00a000\u00a000\u00a000\u00a000\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0mov\u00a0\u00a0\u00a0\u00a0$0x0,%eax<\/li>\n
    15. 400834:\u00a0e8\u00a0af\u00a0fd\u00a0ff\u00a0ff\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0callq\u00a0\u00a04005e8\u00a0<snprintf@plt><\/li>\n<\/ol>\n<\/div>\n

      \u751f\u621032\u4f4d\u6c47\u7f16\u6307\u4ee4\u5982\u4e0b\u6240\u793a\uff1a<\/p>\n

      \n
      \n
      \n

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

      <\/embed><\/div>\n
      <\/div>\n<\/div>\n<\/div>\n
        \n
      1. 80486a8:\u00a0\u00a0\u00a0\u00a0c7\u00a045\u00a0f4\u00a001\u00a000\u00a000\u00a000\u00a0\u00a0\u00a0\u00a0movl\u00a0\u00a0\u00a0$0x1,0xfffffff4(%ebp)<\/li>\n
      2. 80486af:\u00a0\u00a0\u00a0\u00a0c7\u00a045\u00a0e8\u00a004\u00a000\u00a003\u00a000\u00a0\u00a0\u00a0\u00a0movl\u00a0\u00a0\u00a0$0x30004,0xffffffe8(%ebp)<\/li>\n
      3. 80486b6:\u00a0\u00a0\u00a0\u00a0c7\u00a045\u00a0ec\u00a000\u00a000\u00a000\u00a000\u00a0\u00a0\u00a0\u00a0movl\u00a0\u00a0\u00a0$0x0,0xffffffec(%ebp)<\/li>\n
      4. 80486bd:\u00a0\u00a0\u00a0\u00a08d\u00a085\u00a068\u00a0ff\u00a0ff\u00a0ff\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0lea\u00a0\u00a0\u00a0\u00a00xffffff68(%ebp),%eax<\/li>\n
      5. 80486c3:\u00a0\u00a0\u00a0\u00a089\u00a045\u00a0f0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0mov\u00a0\u00a0\u00a0\u00a0%eax,0xfffffff0(%ebp)<\/li>\n
      6. 80486c6:\u00a0\u00a0\u00a0\u00a08b\u00a04d\u00a0f4\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0mov\u00a0\u00a0\u00a0\u00a00xfffffff4(%ebp),%ecx<\/li>\n
      7. 80486c9:\u00a0\u00a0\u00a0\u00a08b\u00a05d\u00a0f0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0mov\u00a0\u00a0\u00a0\u00a00xfffffff0(%ebp),%ebx<\/li>\n
      8. 80486cc:\u00a0\u00a0\u00a0\u00a08b\u00a045\u00a0e8\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0mov\u00a0\u00a0\u00a0\u00a00xffffffe8(%ebp),%eax<\/li>\n
      9. 80486cf:\u00a0\u00a0\u00a0\u00a08b\u00a055\u00a0ec\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0mov\u00a0\u00a0\u00a0\u00a00xffffffec(%ebp),%edx<\/li>\n
      10. 80486d2:\u00a0\u00a0\u00a0\u00a089\u00a04c\u00a024\u00a018\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0mov\u00a0\u00a0\u00a0\u00a0%ecx,0x18(%esp)<\/li>\n
      11. 80486d6:\u00a0\u00a0\u00a0\u00a089\u00a05c\u00a024\u00a014\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0mov\u00a0\u00a0\u00a0\u00a0%ebx,0x14(%esp)<\/li>\n
      12. 80486da:\u00a0\u00a0\u00a0\u00a089\u00a044\u00a024\u00a00c\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0mov\u00a0\u00a0\u00a0\u00a0%eax,0xc(%esp)<\/li>\n
      13. 80486de:\u00a0\u00a0\u00a0\u00a089\u00a054\u00a024\u00a010\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0mov\u00a0\u00a0\u00a0\u00a0%edx,0x10(%esp)<\/li>\n
      14. 80486e2:\u00a0\u00a0\u00a0\u00a0c7\u00a044\u00a024\u00a008\u00a010\u00a088\u00a004\u00a0\u00a0\u00a0\u00a0movl\u00a0\u00a0\u00a0$0x8048810,0x8(%esp)<\/li>\n
      15. 80486e9:\u00a0\u00a0\u00a0\u00a008<\/li>\n
      16. 80486ea:\u00a0\u00a0\u00a0\u00a0c7\u00a044\u00a024\u00a004\u00a080\u00a000\u00a000\u00a0\u00a0\u00a0\u00a0movl\u00a0\u00a0\u00a0$0x80,0x4(%esp)<\/li>\n
      17. 80486f1:\u00a0\u00a0\u00a0\u00a000<\/li>\n
      18. 80486f2:\u00a0\u00a0\u00a0\u00a08d\u00a085\u00a0e8\u00a0fe\u00a0ff\u00a0ff\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0lea\u00a0\u00a0\u00a0\u00a00xfffffee8(%ebp),%eax<\/li>\n
      19. 80486f8:\u00a0\u00a0\u00a0\u00a089\u00a004\u00a024\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0mov\u00a0\u00a0\u00a0\u00a0%eax,(%esp)<\/li>\n
      20. 80486fb:\u00a0\u00a0\u00a0\u00a0e8\u00a0b4\u00a0fd\u00a0ff\u00a0ff\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0call\u00a0\u00a0\u00a080484b4\u00a0<snprintf@plt><\/li>\n<\/ol>\n<\/div>\n

        \u901a\u8fc7\u4ee5\u4e0a\u4e24\u6bb5\u6c47\u7f16\u4ee3\u7801\u53d1\u73b0\uff0c\u5728\u8c03\u7528snprintf\u524d\uff0c64\u4f4d\u4e0b\u5e76\u6ca1\u6709\u5c06\u53c2\u6570push\u5230\u6808\u4e2d\uff0c\u800c\u53ea\u662f\u5c06\u53c2\u6570\u5b58\u5165\u4e86\u5bc4\u5b58\u5668\u4e2d\uff0c\u7531\u4e8e\u5404\u4e2a\u5bc4\u5b58\u5668\u662f\u76f8\u4e92\u72ec\u7acb\u7684\uff0c\u6240\u4ee5\u5373\u4f7f\u5728\u683c\u5f0f\u5316\u8f93\u51fa\u65f6\uff0c\u6307\u5b9a\u7684\u53c2\u6570\u5927\u5c0f\u4e0d\u4e00\u81f4\uff0c\u4e5f\u80fd\u201c\u6b63\u5e38\u201d\u8f93\u51fa(\u5176\u5b9e\u770b\u5230\u7684\u201c\u6b63\u5e38\u201d\uff0c\u662f\u56e0\u4e3ab\u7684\u503c\u8f83\u5c0f\uff0c\u4ecd\u80fd\u4f7f\u7528\u4f4e32\u4f4d\u8868\u793a)\uff0c\u800c\u572832\u4f4d\u4e0b\uff0c\u7531\u4e8e\u53c2\u6570\u8fdb\u884c\u7684\u662f\u5806\u6808\u64cd\u4f5c\uff0c\u6240\u4ee5\u5f53\u6307\u5b9a\u5927\u5c0f\u6709\u8bef\u65f6\uff0c\u8f93\u51fa\u4e5f\u5c31\u4f1a\u5b58\u5728\u95ee\u9898\uff1a\u7531\u4e8eb\u5728\u6808\u4e2d\u5206\u914d\u4e868\u4e2a\u5b57\u8282\uff0c\u800c\u683c\u5f0f\u5316\u65f6\u8f93\u51fa\u65f6\uff0c\u5374\u8ba4\u4e3a\u5176\u53ea\u67094\u4e2a\u5b57\u8282\uff0c\u4ece\u800c\u5bfc\u81f4\u63a5\u4e0b\u6765\uff0c\u5728\u53d6pstr\u503c\u65f6\uff0c\u5b9e\u9645\u4e0a\u53d6\u5230\u7684\u662fb\u503c\u4e2d\u5168\u4e3a0\u7684\u9ad832\u4f4d\uff0c\u800c\u53d6a\u503c\u65f6\uff0c\u53d6\u5230\u7684\u5219\u662fpstr\u7684\u503c\u3002<\/p>\n

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