{"id":115370,"date":"2026-10-12T02:17:11","date_gmt":"2026-10-11T18:17:11","guid":{"rendered":"https:\/\/www.wsisp.com\/helps\/115370.html"},"modified":"2026-10-12T02:17:11","modified_gmt":"2026-10-11T18:17:11","slug":"%e7%ac%ac21%e8%ae%b2%ef%bc%9a%e5%8a%a8%e6%80%81%e5%86%85%e5%ad%98%e7%ae%a1%e7%90%86","status":"publish","type":"post","link":"https:\/\/www.wsisp.com\/helps\/115370.html","title":{"rendered":"\u7b2c21\u8bb2\uff1a\u52a8\u6001\u5185\u5b58\u7ba1\u7406"},"content":{"rendered":"

\u76ee\u5f55<\/h3>\n
  • \u4e3a\u4ec0\u4e48\u8981\u6709\u52a8\u6001\u5185\u5b58\u5206\u914d<\/li>\n
  • malloc \u548c free<\/li>\n
  • calloc \u548c realloc<\/li>\n
  • \u5e38\u89c1\u7684\u52a8\u6001\u5185\u5b58\u7684\u9519\u8bef<\/li>\n
  • \u52a8\u6001\u5185\u5b58\u7ecf\u5178\u7b14\u8bd5\u9898\u5206\u6790<\/li>\n
  • \u67d4\u6027\u6570\u7ec4<\/li>\n
  • \u603b\u7ed3 C\/C++ \u4e2d\u7a0b\u5e8f\u5185\u5b58\u533a\u57df\u5212\u5206<\/li>\n

    \u6b63\u6587\u5f00\u59cb<\/p>\n

    1. \u4e3a\u4ec0\u4e48\u8981\u6709\u52a8\u6001\u5185\u5b58\u5206\u914d<\/h3>\n

    \u6211\u4eec\u5df2\u7ecf\u638c\u63e1\u7684\u5185\u5b58\u5f00\u8f9f\u65b9\u5f0f\u6709：<\/p>\n

    int<\/span> val =<\/span> 20<\/span>;<\/span> \/\/ \u5728\u6808\u7a7a\u95f4\u4e0a\u5f00\u8f9f\u56db\u4e2a\u5b57\u8282<\/span>
    \nchar<\/span> arr[<\/span>10<\/span>]<\/span> =<\/span> {<\/span>0<\/span>}<\/span>;<\/span> \/\/ \u5728\u6808\u7a7a\u95f4\u4e0a\u5f00\u8f9f 10 \u4e2a\u5b57\u8282\u7684\u8fde\u7eed\u7a7a\u95f4<\/span><\/p>\n

    \u4f46\u662f\u4e0a\u8ff0\u7684\u5f00\u8f9f\u7a7a\u95f4\u7684\u65b9\u5f0f\u6709\u4e24\u4e2a\u7279\u70b9：<\/p>\n

      \n
    • \u7a7a\u95f4\u5f00\u8f9f\u5927\u5c0f\u662f\u56fa\u5b9a\u7684\u3002<\/li>\n
    • \u6570\u7ec4\u5728\u58f0\u660e\u7684\u65f6\u5019，\u5fc5\u987b\u6307\u5b9a\u6570\u7ec4\u7684\u957f\u5ea6，\u6570\u7ec4\u7a7a\u95f4\u4e00\u65e6\u786e\u5b9a\u4e86\u5927\u5c0f\u4e0d\u80fd\u8c03\u6574\u3002<\/li>\n<\/ul>\n

      \u4f46\u662f\u5bf9\u4e8e\u7a7a\u95f4\u7684\u9700\u6c42，\u4e0d\u4ec5\u4ec5\u662f\u4e0a\u8ff0\u7684\u60c5\u51b5\u3002\u6709\u65f6\u5019\u6211\u4eec\u9700\u8981\u7684\u7a7a\u95f4\u5927\u5c0f\u5728\u7a0b\u5e8f\u8fd0\u884c\u7684\u65f6\u5019\u624d\u80fd\u77e5\u9053，\u90a3\u6570\u7ec4\u7684\u7f16\u8bd1\u65f6\u5f00\u8f9f\u7a7a\u95f4\u7684\u65b9\u5f0f\u5c31\u4e0d\u80fd\u6ee1\u8db3\u4e86\u3002<\/p>\n

      C \u8bed\u8a00\u5f15\u5165\u4e86\u52a8\u6001\u5185\u5b58\u5f00\u8f9f，\u8ba9\u7a0b\u5e8f\u5458\u81ea\u5df1\u53ef\u4ee5\u7533\u8bf7\u548c\u91ca\u653e\u7a7a\u95f4，\u5c31\u6bd4\u8f83\u7075\u6d3b\u4e86\u3002<\/p>\n

      2. malloc \u548c free<\/h3>\n

      2.1 malloc<\/h4>\n

      C \u8bed\u8a00\u63d0\u4f9b\u4e86\u4e00\u4e2a\u52a8\u6001\u5185\u5b58\u5f00\u8f9f\u7684\u51fd\u6570：<\/p>\n

      void<\/span>*<\/span> malloc<\/span>(<\/span>size_t<\/span> size)<\/span>;<\/span><\/p>\n

      \u8fd9\u4e2a\u51fd\u6570\u5411\u5185\u5b58\u7533\u8bf7\u4e00\u5757\u8fde\u7eed\u53ef\u7528\u7684\u7a7a\u95f4，\u5e76\u8fd4\u56de\u6307\u5411\u8fd9\u5757\u7a7a\u95f4\u7684\u6307\u9488\u3002<\/p>\n

        \n
      • \u5982\u679c\u5f00\u8f9f\u6210\u529f，\u5219\u8fd4\u56de\u4e00\u4e2a\u6307\u5411\u5f00\u8f9f\u597d\u7a7a\u95f4\u7684\u6307\u9488\u3002<\/li>\n
      • \u5982\u679c\u5f00\u8f9f\u5931\u8d25，\u5219\u8fd4\u56de\u4e00\u4e2a NULL \u6307\u9488，\u56e0\u6b64 malloc \u7684\u8fd4\u56de\u503c\u4e00\u5b9a\u8981\u505a\u68c0\u67e5\u3002<\/li>\n
      • \u8fd4\u56de\u503c\u7684\u7c7b\u578b\u662f void*，\u6240\u4ee5 malloc \u51fd\u6570\u5e76\u4e0d\u77e5\u9053\u5f00\u8f9f\u7a7a\u95f4\u7684\u7c7b\u578b，\u5177\u4f53\u5728\u4f7f\u7528\u7684\u65f6\u5019\u4f7f\u7528\u8005\u81ea\u5df1\u6765\u51b3\u5b9a\u3002<\/li>\n
      • \u5982\u679c\u53c2\u6570 size \u4e3a 0，malloc \u7684\u884c\u4e3a\u662f\u6807\u51c6\u672a\u5b9a\u4e49\u7684，\u53d6\u51b3\u4e8e\u7f16\u8bd1\u5668\u3002<\/li>\n<\/ul>\n

        2.2 free<\/h4>\n

        C \u8bed\u8a00\u63d0\u4f9b\u4e86\u53e6\u5916\u4e00\u4e2a\u51fd\u6570 free，\u4e13\u95e8\u662f\u7528\u6765\u505a\u52a8\u6001\u5185\u5b58\u7684\u91ca\u653e\u548c\u56de\u6536\u7684，\u51fd\u6570\u539f\u578b\u5982\u4e0b：<\/p>\n

        void<\/span> free<\/span>(<\/span>void<\/span>*<\/span> ptr)<\/span>;<\/span><\/p>\n

        free \u51fd\u6570\u7528\u6765\u91ca\u653e\u52a8\u6001\u5f00\u8f9f\u7684\u5185\u5b58\u3002<\/p>\n

          \n
        • \u5982\u679c\u53c2\u6570 ptr \u6307\u5411\u7684\u7a7a\u95f4\u4e0d\u662f\u52a8\u6001\u5f00\u8f9f\u7684，\u90a3\u4e48 free \u51fd\u6570\u7684\u884c\u4e3a\u662f\u672a\u5b9a\u4e49\u7684\u3002<\/li>\n
        • \u5982\u679c\u53c2\u6570 ptr \u662f NULL \u6307\u9488，\u5219\u51fd\u6570\u4ec0\u4e48\u4e8b\u90fd\u4e0d\u505a\u3002<\/li>\n<\/ul>\n

          malloc \u548c free \u90fd\u58f0\u660e\u5728 stdlib.h \u5934\u6587\u4ef6\u4e2d\u3002<\/p>\n

          \u4e3e\u4e2a\u4f8b\u5b50：<\/p>\n

          #<\/span>include<\/span> <stdio.h><\/span><\/span>
          \n#<\/span>include<\/span> <stdlib.h><\/span><\/span><\/p>\n

          int<\/span> main<\/span>(<\/span>)<\/span>
          \n{<\/span>
          \n int<\/span> num =<\/span> 0<\/span>;<\/span>
          \n scanf<\/span>(<\/span>"%d"<\/span>,<\/span> &<\/span>num)<\/span>;<\/span>
          \n int<\/span> arr[<\/span>num]<\/span> =<\/span> {<\/span>0<\/span>}<\/span>;<\/span>
          \n int<\/span>*<\/span> ptr =<\/span> NULL<\/span>;<\/span>
          \n ptr =<\/span> (<\/span>int<\/span>*<\/span>)<\/span>malloc<\/span>(<\/span>num *<\/span> sizeof<\/span>(<\/span>int<\/span>)<\/span>)<\/span>;<\/span>
          \n if<\/span> (<\/span>NULL<\/span> !=<\/span> ptr)<\/span> \/\/ \u5224\u65ad ptr \u6307\u9488\u662f\u5426\u4e3a\u7a7a<\/span>
          \n {<\/span>
          \n int<\/span> i =<\/span> 0<\/span>;<\/span>
          \n for<\/span> (<\/span>i =<\/span> 0<\/span>;<\/span> i <<\/span> num;<\/span> i++<\/span>)<\/span>
          \n {<\/span>
          \n *<\/span>(<\/span>ptr +<\/span> i)<\/span> =<\/span> 0<\/span>;<\/span>
          \n }<\/span>
          \n }<\/span>
          \n free<\/span>(<\/span>ptr)<\/span>;<\/span> \/\/ \u91ca\u653e ptr \u6240\u6307\u5411\u7684\u52a8\u6001\u5185\u5b58<\/span>
          \n ptr =<\/span> NULL<\/span>;<\/span> \/\/ \u662f\u5426\u6709\u5fc5\u8981？<\/span>
          \n return<\/span> 0<\/span>;<\/span>
          \n}<\/span><\/p>\n

          3. calloc \u548c realloc<\/h3>\n

          3.1 calloc<\/h4>\n

          C \u8bed\u8a00\u8fd8\u63d0\u4f9b\u4e86\u4e00\u4e2a\u51fd\u6570\u53eb calloc，calloc \u51fd\u6570\u4e5f\u7528\u6765\u52a8\u6001\u5185\u5b58\u5206\u914d\u3002\u539f\u578b\u5982\u4e0b：<\/p>\n

          void<\/span>*<\/span> calloc<\/span>(<\/span>size_t<\/span> num,<\/span> size_t<\/span> size)<\/span>;<\/span><\/p>\n

            \n
          • \u51fd\u6570\u7684\u529f\u80fd\u662f\u4e3a num \u4e2a\u5927\u5c0f\u4e3a size \u7684\u5143\u7d20\u5f00\u8f9f\u4e00\u5757\u7a7a\u95f4，\u5e76\u4e14\u628a\u7a7a\u95f4\u7684\u6bcf\u4e2a\u5b57\u8282\u521d\u59cb\u5316\u4e3a 0\u3002<\/li>\n
          • \u4e0e\u51fd\u6570 malloc \u7684\u533a\u522b\u53ea\u5728\u4e8e calloc \u4f1a\u5728\u8fd4\u56de\u5730\u5740\u4e4b\u524d\u628a\u7533\u8bf7\u7684\u7a7a\u95f4\u7684\u6bcf\u4e2a\u5b57\u8282\u521d\u59cb\u5316\u4e3a\u5168 0\u3002<\/li>\n<\/ul>\n

            \u4e3e\u4e2a\u4f8b\u5b50：<\/p>\n

            #<\/span>include<\/span> <stdio.h><\/span><\/span>
            \n#<\/span>include<\/span> <stdlib.h><\/span><\/span><\/p>\n

            int<\/span> main<\/span>(<\/span>)<\/span>
            \n{<\/span>
            \n int<\/span> *<\/span>p =<\/span> (<\/span>int<\/span>*<\/span>)<\/span>calloc<\/span>(<\/span>10<\/span>,<\/span> sizeof<\/span>(<\/span>int<\/span>)<\/span>)<\/span>;<\/span>
            \n if<\/span> (<\/span>NULL<\/span> !=<\/span> p)<\/span>
            \n {<\/span>
            \n int<\/span> i =<\/span> 0<\/span>;<\/span>
            \n for<\/span> (<\/span>i =<\/span> 0<\/span>;<\/span> i <<\/span> 10<\/span>;<\/span> i++<\/span>)<\/span>
            \n {<\/span>
            \n printf<\/span>(<\/span>"%d "<\/span>,<\/span> *<\/span>(<\/span>p +<\/span> i)<\/span>)<\/span>;<\/span>
            \n }<\/span>
            \n }<\/span>
            \n free<\/span>(<\/span>p)<\/span>;<\/span>
            \n p =<\/span> NULL<\/span>;<\/span>
            \n return<\/span> 0<\/span>;<\/span>
            \n}<\/span><\/p>\n

            \u8f93\u51fa\u7ed3\u679c：<\/p>\n

            0 0 0 0 0 0 0 0 0 0<\/p>\n

            \u6240\u4ee5\u5982\u679c\u6211\u4eec\u5bf9\u7533\u8bf7\u7684\u5185\u5b58\u7a7a\u95f4\u7684\u5185\u5bb9\u8981\u6c42\u521d\u59cb\u5316，\u90a3\u4e48\u53ef\u4ee5\u5f88\u65b9\u4fbf\u5730\u4f7f\u7528 calloc \u51fd\u6570\u6765\u5b8c\u6210\u4efb\u52a1\u3002<\/p>\n

            3.2 realloc<\/h4>\n
              \n
            • realloc \u51fd\u6570\u7684\u51fa\u73b0\u8ba9\u52a8\u6001\u5185\u5b58\u7ba1\u7406\u66f4\u52a0\u7075\u6d3b\u3002<\/li>\n
            • \u6709\u65f6\u5019\u6211\u4eec\u53d1\u73b0\u8fc7\u53bb\u7533\u8bf7\u7684\u7a7a\u95f4\u592a\u5c0f\u4e86，\u6709\u65f6\u5019\u6211\u4eec\u53c8\u4f1a\u89c9\u5f97\u7533\u8bf7\u7684\u7a7a\u95f4\u8fc7\u5927\u4e86\u3002\u4e3a\u4e86\u5408\u7406\u5730\u4f7f\u7528\u5185\u5b58，\u6211\u4eec\u4e00\u5b9a\u4f1a\u5bf9\u5185\u5b58\u7684\u5927\u5c0f\u505a\u7075\u6d3b\u7684\u8c03\u6574，\u90a3\u4e48 realloc \u51fd\u6570\u5c31\u53ef\u4ee5\u505a\u5230\u5bf9\u52a8\u6001\u5f00\u8f9f\u5185\u5b58\u5927\u5c0f\u7684\u8c03\u6574\u3002<\/li>\n<\/ul>\n

              \u51fd\u6570\u539f\u578b\u5982\u4e0b：<\/p>\n

              void<\/span>*<\/span> realloc<\/span>(<\/span>void<\/span>*<\/span> ptr,<\/span> size_t<\/span> size)<\/span>;<\/span><\/p>\n

                \n
              • ptr \u662f\u8981\u8c03\u6574\u7684\u5185\u5b58\u5730\u5740\u3002<\/li>\n
              • size \u662f\u8c03\u6574\u4e4b\u540e\u7684\u65b0\u5927\u5c0f\u3002<\/li>\n
              • \u8fd4\u56de\u503c\u4e3a\u8c03\u6574\u4e4b\u540e\u7684\u5185\u5b58\u8d77\u59cb\u4f4d\u7f6e\u3002<\/li>\n
              • \u8fd9\u4e2a\u51fd\u6570\u5728\u8c03\u6574\u539f\u5185\u5b58\u7a7a\u95f4\u5927\u5c0f\u7684\u57fa\u7840\u4e0a，\u8fd8\u4f1a\u5c06\u539f\u6765\u5185\u5b58\u4e2d\u7684\u6570\u636e\u79fb\u52a8\u5230\u65b0\u7684\u7a7a\u95f4\u3002<\/li>\n
              • realloc \u5728\u8c03\u6574\u5185\u5b58\u7a7a\u95f4\u65f6\u5b58\u5728\u4e24\u79cd\u60c5\u51b5：\n
                  \n
                • \u60c5\u51b5 1：\u539f\u6709\u7a7a\u95f4\u4e4b\u540e\u6709\u8db3\u591f\u5927\u7684\u7a7a\u95f4\u3002<\/li>\n
                • \u60c5\u51b5 2：\u539f\u6709\u7a7a\u95f4\u4e4b\u540e\u6ca1\u6709\u8db3\u591f\u5927\u7684\u7a7a\u95f4\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n

                  \"\"<\/p>\n

                  \u60c5\u51b5 1<\/h5>\n

                  \u5f53\u662f\u60c5\u51b5 1 \u7684\u65f6\u5019，\u8981\u6269\u5c55\u5185\u5b58\u5c31\u76f4\u63a5\u5728\u539f\u6709\u5185\u5b58\u4e4b\u540e\u8ffd\u52a0\u7a7a\u95f4，\u539f\u6765\u7a7a\u95f4\u7684\u6570\u636e\u4e0d\u53d1\u751f\u53d8\u5316\u3002<\/p>\n

                  \u60c5\u51b5 2<\/h5>\n

                  \u5f53\u662f\u60c5\u51b5 2 \u7684\u65f6\u5019，\u539f\u6709\u7a7a\u95f4\u4e4b\u540e\u6ca1\u6709\u8db3\u591f\u591a\u7684\u7a7a\u95f4\u65f6，\u6269\u5c55\u7684\u65b9\u6cd5\u662f：\u5728\u5806\u7a7a\u95f4\u4e0a\u53e6\u627e\u4e00\u4e2a\u5408\u9002\u5927\u5c0f\u7684\u8fde\u7eed\u7a7a\u95f4\u6765\u4f7f\u7528\u3002\u8fd9\u6837\u51fd\u6570\u8fd4\u56de\u7684\u662f\u4e00\u4e2a\u65b0\u7684\u5185\u5b58\u5730\u5740\u3002<\/p>\n

                  \u7531\u4e8e\u4e0a\u8ff0\u7684\u4e24\u79cd\u60c5\u51b5，realloc \u51fd\u6570\u7684\u4f7f\u7528\u5c31\u8981\u6ce8\u610f\u4e00\u4e9b\u3002<\/p>\n

                  #<\/span>include<\/span> <stdio.h><\/span><\/span>
                  \n#<\/span>include<\/span> <stdlib.h><\/span><\/span><\/p>\n

                  int<\/span> main<\/span>(<\/span>)<\/span>
                  \n{<\/span>
                  \n int<\/span> *<\/span>ptr =<\/span> (<\/span>int<\/span>*<\/span>)<\/span>malloc<\/span>(<\/span>100<\/span>)<\/span>;<\/span>
                  \n if<\/span> (<\/span>ptr !=<\/span> NULL<\/span>)<\/span>
                  \n {<\/span>
                  \n \/\/ \u4e1a\u52a1\u5904\u7406<\/span>
                  \n }<\/span>
                  \n else<\/span>
                  \n {<\/span>
                  \n return<\/span> 1<\/span>;<\/span>
                  \n }<\/span><\/p>\n

                  \/\/ \u6269\u5c55\u5bb9\u91cf<\/span><\/p>\n

                  \/\/ \u4ee3\u7801 1 – \u76f4\u63a5\u5c06 realloc \u7684\u8fd4\u56de\u503c\u653e\u5230 ptr \u4e2d<\/span>
                  \n ptr =<\/span> (<\/span>int<\/span>*<\/span>)<\/span>realloc<\/span>(<\/span>ptr,<\/span> 1000<\/span>)<\/span>;<\/span> \/\/ \u8fd9\u6837\u53ef\u4ee5\u5417？（\u5982\u679c\u7533\u8bf7\u5931\u8d25\u4f1a\u5982\u4f55？）<\/span><\/p>\n

                  \/\/ \u4ee3\u7801 2 – \u5148\u5c06 realloc \u51fd\u6570\u7684\u8fd4\u56de\u503c\u653e\u5728 p \u4e2d，\u4e0d\u4e3a NULL，\u518d\u653e\u5230 ptr \u4e2d<\/span>
                  \n int<\/span> *<\/span>p =<\/span> NULL<\/span>;<\/span>
                  \n p =<\/span> realloc<\/span>(<\/span>ptr,<\/span> 1000<\/span>)<\/span>;<\/span>
                  \n if<\/span> (<\/span>p !=<\/span> NULL<\/span>)<\/span>
                  \n {<\/span>
                  \n ptr =<\/span> p;<\/span>
                  \n }<\/span><\/p>\n

                  \/\/ \u4e1a\u52a1\u5904\u7406<\/span>
                  \n free<\/span>(<\/span>ptr)<\/span>;<\/span>
                  \n return<\/span> 0<\/span>;<\/span>
                  \n}<\/span><\/p>\n

                  4. \u5e38\u89c1\u7684\u52a8\u6001\u5185\u5b58\u7684\u9519\u8bef<\/h3>\n

                  4.1 \u5bf9 NULL \u6307\u9488\u7684\u89e3\u5f15\u7528\u64cd\u4f5c<\/h4>\n

                  void<\/span> test<\/span>(<\/span>)<\/span>
                  \n{<\/span>
                  \n int<\/span> *<\/span>p =<\/span> (<\/span>int<\/span> *<\/span>)<\/span>malloc<\/span>(<\/span>INT_MAX \/<\/span> 4<\/span>)<\/span>;<\/span>
                  \n *<\/span>p =<\/span> 20<\/span>;<\/span> \/\/ \u5982\u679c p \u7684\u503c\u662f NULL，\u5c31\u4f1a\u6709\u95ee\u9898<\/span>
                  \n free<\/span>(<\/span>p)<\/span>;<\/span>
                  \n}<\/span><\/p>\n

                  4.2 \u5bf9\u52a8\u6001\u5f00\u8f9f\u7a7a\u95f4\u7684\u8d8a\u754c\u8bbf\u95ee<\/h4>\n

                  void<\/span> test<\/span>(<\/span>)<\/span>
                  \n{<\/span>
                  \n int<\/span> i =<\/span> 0<\/span>;<\/span>
                  \n int<\/span> *<\/span>p =<\/span> (<\/span>int<\/span> *<\/span>)<\/span>malloc<\/span>(<\/span>10<\/span> *<\/span> sizeof<\/span>(<\/span>int<\/span>)<\/span>)<\/span>;<\/span>
                  \n if<\/span> (<\/span>NULL<\/span> ==<\/span> p)<\/span>
                  \n {<\/span>
                  \n exit<\/span>(<\/span>EXIT_FAILURE)<\/span>;<\/span>
                  \n }<\/span>
                  \n for<\/span> (<\/span>i =<\/span> 0<\/span>;<\/span> i <=<\/span> 10<\/span>;<\/span> i++<\/span>)<\/span>
                  \n {<\/span>
                  \n *<\/span>(<\/span>p +<\/span> i)<\/span> =<\/span> i;<\/span> \/\/ \u5f53 i \u662f 10 \u7684\u65f6\u5019\u8d8a\u754c\u8bbf\u95ee<\/span>
                  \n }<\/span>
                  \n free<\/span>(<\/span>p)<\/span>;<\/span>
                  \n}<\/span><\/p>\n

                  4.3 \u5bf9\u975e\u52a8\u6001\u5f00\u8f9f\u5185\u5b58\u4f7f\u7528 free \u91ca\u653e<\/h4>\n

                  void<\/span> test<\/span>(<\/span>)<\/span>
                  \n{<\/span>
                  \n int<\/span> a =<\/span> 10<\/span>;<\/span>
                  \n int<\/span> *<\/span>p =<\/span> &<\/span>a;<\/span>
                  \n free<\/span>(<\/span>p)<\/span>;<\/span> \/\/ ok?<\/span>
                  \n}<\/span><\/p>\n

                  4.4 \u4f7f\u7528 free \u91ca\u653e\u4e00\u5757\u52a8\u6001\u5f00\u8f9f\u5185\u5b58\u7684\u4e00\u90e8\u5206<\/h4>\n

                  void<\/span> test<\/span>(<\/span>)<\/span>
                  \n{<\/span>
                  \n int<\/span> *<\/span>p =<\/span> (<\/span>int<\/span> *<\/span>)<\/span>malloc<\/span>(<\/span>100<\/span>)<\/span>;<\/span>
                  \n p++<\/span>;<\/span>
                  \n free<\/span>(<\/span>p)<\/span>;<\/span> \/\/ p \u4e0d\u518d\u6307\u5411\u52a8\u6001\u5185\u5b58\u7684\u8d77\u59cb\u4f4d\u7f6e<\/span>
                  \n}<\/span><\/p>\n

                  4.5 \u5bf9\u540c\u4e00\u5757\u52a8\u6001\u5185\u5b58\u591a\u6b21\u91ca\u653e<\/h4>\n

                  void<\/span> test<\/span>(<\/span>)<\/span>
                  \n{<\/span>
                  \n int<\/span> *<\/span>p =<\/span> (<\/span>int<\/span> *<\/span>)<\/span>malloc<\/span>(<\/span>100<\/span>)<\/span>;<\/span>
                  \n free<\/span>(<\/span>p)<\/span>;<\/span>
                  \n free<\/span>(<\/span>p)<\/span>;<\/span> \/\/ \u91cd\u590d\u91ca\u653e<\/span>
                  \n}<\/span><\/p>\n

                  4.6 \u52a8\u6001\u5f00\u8f9f\u5185\u5b58\u5fd8\u8bb0\u91ca\u653e（\u5185\u5b58\u6cc4\u6f0f）<\/h4>\n

                  void<\/span> test<\/span>(<\/span>)<\/span>
                  \n{<\/span>
                  \n int<\/span> *<\/span>p =<\/span> (<\/span>int<\/span> *<\/span>)<\/span>malloc<\/span>(<\/span>100<\/span>)<\/span>;<\/span>
                  \n if<\/span> (<\/span>NULL<\/span> !=<\/span> p)<\/span>
                  \n {<\/span>
                  \n *<\/span>p =<\/span> 20<\/span>;<\/span>
                  \n }<\/span>
                  \n}<\/span><\/p>\n

                  int<\/span> main<\/span>(<\/span>)<\/span>
                  \n{<\/span>
                  \n test<\/span>(<\/span>)<\/span>;<\/span>
                  \n while<\/span> (<\/span>1<\/span>)<\/span>;<\/span>
                  \n}<\/span><\/p>\n

                  \u5fd8\u8bb0\u91ca\u653e\u4e0d\u518d\u4f7f\u7528\u7684\u52a8\u6001\u5f00\u8f9f\u7684\u7a7a\u95f4\u5c31\u4f1a\u9020\u6210\u5185\u5b58\u6cc4\u6f0f\u3002<\/p>\n

                  \u5207\u8bb0：\u52a8\u6001\u5f00\u8f9f\u7684\u7a7a\u95f4\u4e00\u5b9a\u8981\u91ca\u653e，\u5e76\u4e14\u6b63\u786e\u91ca\u653e\u3002<\/p>\n

                  5. \u52a8\u6001\u5185\u5b58\u7ecf\u5178\u7b14\u8bd5\u9898\u5206\u6790<\/h3>\n

                  5.1 \u9898\u76ee 1<\/h4>\n

                  void<\/span> GetMemory<\/span>(<\/span>char<\/span> *<\/span>p)<\/span>
                  \n{<\/span>
                  \n p =<\/span> (<\/span>char<\/span> *<\/span>)<\/span>malloc<\/span>(<\/span>100<\/span>)<\/span>;<\/span>
                  \n}<\/span><\/p>\n

                  void<\/span> Test<\/span>(<\/span>void<\/span>)<\/span>
                  \n{<\/span>
                  \n char<\/span> *<\/span>str =<\/span> NULL<\/span>;<\/span>
                  \n GetMemory<\/span>(<\/span>str)<\/span>;<\/span>
                  \n strcpy<\/span>(<\/span>str,<\/span> "hello world"<\/span>)<\/span>;<\/span>
                  \n printf<\/span>(<\/span>str)<\/span>;<\/span>
                  \n}<\/span><\/p>\n

                  \u8bf7\u95ee\u8fd0\u884c Test \u51fd\u6570\u4f1a\u6709\u4ec0\u4e48\u6837\u7684\u7ed3\u679c？<\/p>\n

                  5.2 \u9898\u76ee 2<\/h4>\n

                  char<\/span> *<\/span>GetMemory<\/span>(<\/span>void<\/span>)<\/span>
                  \n{<\/span>
                  \n char<\/span> p[<\/span>]<\/span> =<\/span> "hello world"<\/span>;<\/span>
                  \n return<\/span> p;<\/span>
                  \n}<\/span><\/p>\n

                  void<\/span> Test<\/span>(<\/span>void<\/span>)<\/span>
                  \n{<\/span>
                  \n char<\/span> *<\/span>str =<\/span> NULL<\/span>;<\/span>
                  \n str =<\/span> GetMemory<\/span>(<\/span>)<\/span>;<\/span>
                  \n printf<\/span>(<\/span>str)<\/span>;<\/span>
                  \n}<\/span><\/p>\n

                  \u8bf7\u95ee\u8fd0\u884c Test \u51fd\u6570\u4f1a\u6709\u4ec0\u4e48\u6837\u7684\u7ed3\u679c？<\/p>\n

                  5.3 \u9898\u76ee 3<\/h4>\n

                  void<\/span> GetMemory<\/span>(<\/span>char<\/span> *<\/span>*<\/span>p,<\/span> int<\/span> num)<\/span>
                  \n{<\/span>
                  \n *<\/span>p =<\/span> (<\/span>char<\/span> *<\/span>)<\/span>malloc<\/span>(<\/span>num)<\/span>;<\/span>
                  \n}<\/span><\/p>\n

                  void<\/span> Test<\/span>(<\/span>void<\/span>)<\/span>
                  \n{<\/span>
                  \n char<\/span> *<\/span>str =<\/span> NULL<\/span>;<\/span>
                  \n GetMemory<\/span>(<\/span>&<\/span>str,<\/span> 100<\/span>)<\/span>;<\/span>
                  \n strcpy<\/span>(<\/span>str,<\/span> "hello"<\/span>)<\/span>;<\/span>
                  \n printf<\/span>(<\/span>str)<\/span>;<\/span>
                  \n}<\/span><\/p>\n

                  \u8bf7\u95ee\u8fd0\u884c Test \u51fd\u6570\u4f1a\u6709\u4ec0\u4e48\u6837\u7684\u7ed3\u679c？<\/p>\n

                  5.4 \u9898\u76ee 4<\/h4>\n

                  void<\/span> Test<\/span>(<\/span>void<\/span>)<\/span>
                  \n{<\/span>
                  \n char<\/span> *<\/span>str =<\/span> (<\/span>char<\/span> *<\/span>)<\/span>malloc<\/span>(<\/span>100<\/span>)<\/span>;<\/span>
                  \n strcpy<\/span>(<\/span>str,<\/span> "hello"<\/span>)<\/span>;<\/span>
                  \n free<\/span>(<\/span>str)<\/span>;<\/span>
                  \n if<\/span> (<\/span>str !=<\/span> NULL<\/span>)<\/span>
                  \n {<\/span>
                  \n strcpy<\/span>(<\/span>str,<\/span> "world"<\/span>)<\/span>;<\/span>
                  \n printf<\/span>(<\/span>str)<\/span>;<\/span>
                  \n }<\/span>
                  \n}<\/span><\/p>\n

                  \u8bf7\u95ee\u8fd0\u884c Test \u51fd\u6570\u4f1a\u6709\u4ec0\u4e48\u6837\u7684\u7ed3\u679c？<\/p>\n

                  6. \u67d4\u6027\u6570\u7ec4<\/h3>\n

                  \u4e5f\u8bb8\u4f60\u4ece\u6765\u6ca1\u6709\u542c\u8bf4\u8fc7**\u67d4\u6027\u6570\u7ec4（flexible array）**\u8fd9\u4e2a\u6982\u5ff5，\u4f46\u662f\u5b83\u786e\u5b9e\u662f\u5b58\u5728\u7684\u3002<\/p>\n

                  C99 \u4e2d，\u7ed3\u6784\u4e2d\u7684\u6700\u540e\u4e00\u4e2a\u5143\u7d20\u5141\u8bb8\u662f\u672a\u77e5\u5927\u5c0f\u7684\u6570\u7ec4，\u8fd9\u5c31\u53eb\u505a\u201c\u67d4\u6027\u6570\u7ec4\u201d\u6210\u5458\u3002<\/p>\n

                  \u4f8b\u5982：<\/p>\n

                  typedef<\/span> struct<\/span> st_type<\/span>
                  \n{<\/span>
                  \n int<\/span> i;<\/span>
                  \n int<\/span> a[<\/span>0<\/span>]<\/span>;<\/span> \/\/ \u67d4\u6027\u6570\u7ec4\u6210\u5458<\/span>
                  \n}<\/span> type_a;<\/span><\/p>\n

                  \u6709\u4e9b\u7f16\u8bd1\u5668\u4f1a\u62a5\u9519\u65e0\u6cd5\u7f16\u8bd1，\u53ef\u4ee5\u6539\u6210：<\/p>\n

                  typedef<\/span> struct<\/span> st_type<\/span>
                  \n{<\/span>
                  \n int<\/span> i;<\/span>
                  \n int<\/span> a[<\/span>]<\/span>;<\/span> \/\/ \u67d4\u6027\u6570\u7ec4\u6210\u5458<\/span>
                  \n}<\/span> type_a;<\/span><\/p>\n

                  6.1 \u67d4\u6027\u6570\u7ec4\u7684\u7279\u70b9<\/h4>\n
                    \n
                  • \u7ed3\u6784\u4e2d\u7684\u67d4\u6027\u6570\u7ec4\u6210\u5458\u524d\u9762\u5fc5\u987b\u81f3\u5c11\u6709\u4e00\u4e2a\u5176\u4ed6\u6210\u5458\u3002<\/li>\n
                  • sizeof \u8fd4\u56de\u7684\u8fd9\u79cd\u7ed3\u6784\u5927\u5c0f\u4e0d\u5305\u62ec\u67d4\u6027\u6570\u7ec4\u7684\u5185\u5b58\u3002<\/li>\n
                  • \u5305\u542b\u67d4\u6027\u6570\u7ec4\u6210\u5458\u7684\u7ed3\u6784\u7528 malloc() \u51fd\u6570\u8fdb\u884c\u5185\u5b58\u7684\u52a8\u6001\u5206\u914d，\u5e76\u4e14\u5206\u914d\u7684\u5185\u5b58\u5e94\u8be5\u5927\u4e8e\u7ed3\u6784\u7684\u5927\u5c0f，\u4ee5\u9002\u5e94\u67d4\u6027\u6570\u7ec4\u7684\u9884\u671f\u5927\u5c0f\u3002<\/li>\n<\/ul>\n

                    \u4f8b\u5982：<\/p>\n

                    typedef<\/span> struct<\/span> st_type<\/span>
                    \n{<\/span>
                    \n int<\/span> i;<\/span>
                    \n int<\/span> a[<\/span>0<\/span>]<\/span>;<\/span> \/\/ \u67d4\u6027\u6570\u7ec4\u6210\u5458<\/span>
                    \n}<\/span> type_a;<\/span><\/p>\n

                    int<\/span> main<\/span>(<\/span>)<\/span>
                    \n{<\/span>
                    \n printf<\/span>(<\/span>"%d | "<\/span>,<\/span> sizeof<\/span>(<\/span>type_a)<\/span>)<\/span>;<\/span> \/\/ \u8f93\u51fa\u7684\u662f 4<\/span>
                    \n return<\/span> 0<\/span>;<\/span>
                    \n}<\/span><\/p>\n

                    6.2 \u67d4\u6027\u6570\u7ec4\u7684\u4f7f\u7528<\/h4>\n

                    \/\/ \u4ee3\u7801 1<\/span>
                    \n#<\/span>include<\/span> <stdio.h><\/span><\/span>
                    \n#<\/span>include<\/span> <stdlib.h><\/span><\/span><\/p>\n

                    int<\/span> main<\/span>(<\/span>)<\/span>
                    \n{<\/span>
                    \n int<\/span> i =<\/span> 0<\/span>;<\/span>
                    \n type_a *<\/span>p =<\/span> (<\/span>type_a*<\/span>)<\/span>malloc<\/span>(<\/span>sizeof<\/span>(<\/span>type_a)<\/span> +<\/span> 100<\/span> *<\/span> sizeof<\/span>(<\/span>int<\/span>)<\/span>)<\/span>;<\/span>
                    \n \/\/ \u4e1a\u52a1\u5904\u7406<\/span>
                    \n p-><\/span>i =<\/span> 100<\/span>;<\/span>
                    \n for<\/span> (<\/span>i =<\/span> 0<\/span>;<\/span> i <<\/span> 100<\/span>;<\/span> i++<\/span>)<\/span>
                    \n {<\/span>
                    \n p-><\/span>a[<\/span>i]<\/span> =<\/span> i;<\/span>
                    \n }<\/span>
                    \n free<\/span>(<\/span>p)<\/span>;<\/span>
                    \n return<\/span> 0<\/span>;<\/span>
                    \n}<\/span><\/p>\n

                    \u8fd9\u6837\u67d4\u6027\u6570\u7ec4\u6210\u5458 a，\u76f8\u5f53\u4e8e\u83b7\u5f97\u4e86 100 \u4e2a\u6574\u578b\u5143\u7d20\u7684\u8fde\u7eed\u7a7a\u95f4\u3002<\/p>\n

                    6.3 \u67d4\u6027\u6570\u7ec4\u7684\u4f18\u52bf<\/h4>\n

                    \u4e0a\u8ff0\u7684 type_a \u7ed3\u6784\u4e5f\u53ef\u4ee5\u8bbe\u8ba1\u4e3a\u4e0b\u9762\u7684\u7ed3\u6784，\u4e5f\u80fd\u5b8c\u6210\u540c\u6837\u7684\u6548\u679c\u3002<\/p>\n

                    \/\/ \u4ee3\u7801 2<\/span>
                    \n#<\/span>include<\/span> <stdio.h><\/span><\/span>
                    \n#<\/span>include<\/span> <stdlib.h><\/span><\/span><\/p>\n

                    typedef<\/span> struct<\/span> st_type<\/span>
                    \n{<\/span>
                    \n int<\/span> i;<\/span>
                    \n int<\/span> *<\/span>p_a;<\/span>
                    \n}<\/span> type_a;<\/span><\/p>\n

                    int<\/span> main<\/span>(<\/span>)<\/span>
                    \n{<\/span>
                    \n int<\/span> i =<\/span> 0<\/span>;<\/span>
                    \n type_a *<\/span>p =<\/span> (<\/span>type_a *<\/span>)<\/span>malloc<\/span>(<\/span>sizeof<\/span>(<\/span>type_a)<\/span>)<\/span>;<\/span>
                    \n p-><\/span>i =<\/span> 100<\/span>;<\/span>
                    \n p-><\/span>p_a =<\/span> (<\/span>int<\/span> *<\/span>)<\/span>malloc<\/span>(<\/span>p-><\/span>i *<\/span> sizeof<\/span>(<\/span>int<\/span>)<\/span>)<\/span>;<\/span><\/p>\n

                    \/\/ \u4e1a\u52a1\u5904\u7406<\/span>
                    \n for<\/span> (<\/span>i =<\/span> 0<\/span>;<\/span> i <<\/span> 100<\/span>;<\/span> i++<\/span>)<\/span>
                    \n {<\/span>
                    \n p-><\/span>p_a[<\/span>i]<\/span> =<\/span> i;<\/span>
                    \n }<\/span><\/p>\n

                    \/\/ \u91ca\u653e\u7a7a\u95f4<\/span>
                    \n free<\/span>(<\/span>p-><\/span>p_a)<\/span>;<\/span>
                    \n p-><\/span>p_a =<\/span> NULL<\/span>;<\/span>
                    \n free<\/span>(<\/span>p)<\/span>;<\/span>
                    \n p =<\/span> NULL<\/span>;<\/span>
                    \n return<\/span> 0<\/span>;<\/span>
                    \n}<\/span><\/p>\n

                    \u4e0a\u8ff0\u4ee3\u7801 1\u548c\u4ee3\u7801 2\u53ef\u4ee5\u5b8c\u6210\u540c\u6837\u7684\u529f\u80fd，\u4f46\u662f\u65b9\u6cd5 1\u7684\u5b9e\u73b0\u6709\u4e24\u4e2a\u597d\u5904：<\/p>\n

                    **\u7b2c\u4e00\u4e2a\u597d\u5904\u662f：**\u65b9\u4fbf\u5185\u5b58\u91ca\u653e<\/p>\n

                    \u5982\u679c\u6211\u4eec\u7684\u4ee3\u7801\u662f\u5728\u4e00\u4e2a\u7ed9\u522b\u4eba\u7528\u7684\u51fd\u6570\u4e2d，\u4f60\u5728\u91cc\u9762\u505a\u4e86\u4e8c\u6b21\u5185\u5b58\u5206\u914d，\u5e76\u628a\u6574\u4e2a\u7ed3\u6784\u4f53\u8fd4\u56de\u7ed9\u7528\u6237\u3002\u7528\u6237\u8c03\u7528 free \u53ef\u4ee5\u91ca\u653e\u7ed3\u6784\u4f53，\u4f46\u662f\u7528\u6237\u5e76\u4e0d\u77e5\u9053\u8fd9\u4e2a\u7ed3\u6784\u4f53\u5185\u7684\u6210\u5458\u4e5f\u9700\u8981 free，\u6240\u4ee5\u4f60\u4e0d\u80fd\u6307\u671b\u7528\u6237\u6765\u53d1\u73b0\u8fd9\u4e2a\u4e8b\u3002\u6240\u4ee5，\u5982\u679c\u6211\u4eec\u628a\u7ed3\u6784\u4f53\u7684\u5185\u5b58\u4ee5\u53ca\u5176\u6210\u5458\u8981\u7684\u5185\u5b58\u4e00\u6b21\u6027\u5206\u914d\u597d\u4e86，\u5e76\u8fd4\u56de\u7ed9\u7528\u6237\u4e00\u4e2a\u7ed3\u6784\u4f53\u6307\u9488，\u7528\u6237\u505a\u4e00\u6b21 free \u5c31\u53ef\u4ee5\u628a\u6240\u6709\u7684\u5185\u5b58\u4e5f\u7ed9\u91ca\u653e\u6389\u3002<\/p>\n

                    \u7b2c\u4e8c\u4e2a\u597d\u5904\u662f：\u8fd9\u6837\u6709\u5229\u4e8e\u8bbf\u95ee\u901f\u5ea6\u3002<\/p>\n

                    \u8fde\u7eed\u7684\u5185\u5b58\u6709\u76ca\u4e8e\u63d0\u9ad8\u8bbf\u95ee\u901f\u5ea6，\u4e5f\u6709\u76ca\u4e8e\u51cf\u5c11\u5185\u5b58\u788e\u7247\u3002（\u5176\u5b9e，\u6211\u4e2a\u4eba\u89c9\u5f97\u4e5f\u6ca1\u591a\u9ad8\u4e86，\u53cd\u6b63\u4f60\u8dd1\u4e0d\u4e86\u8981\u7528\u505a\u504f\u79fb\u91cf\u7684\u52a0\u6cd5\u6765\u5bfb\u5740）<\/p>\n

                    \u6269\u5c55\u9605\u8bfb：<\/p>\n

                    C \u8bed\u8a00\u7ed3\u6784\u4f53\u91cc\u7684\u6570\u7ec4\u548c\u6307\u9488<\/p>\n

                    7. \u603b\u7ed3 C\/C++ \u4e2d\u7a0b\u5e8f\u5185\u5b58\u533a\u57df\u5212\u5206<\/h3>\n

                    \"\"<\/p>\n

                    C\/C++ \u7a0b\u5e8f\u5185\u5b58\u5206\u914d\u7684\u51e0\u4e2a\u533a\u57df：<\/p>\n

                  • \u6808\u533a（stack）：\u5728\u6267\u884c\u51fd\u6570\u65f6，\u51fd\u6570\u5185\u5c40\u90e8\u53d8\u91cf\u7684\u5b58\u50a8\u5355\u5143\u90fd\u53ef\u4ee5\u5728\u6808\u4e0a\u521b\u5efa，\u51fd\u6570\u6267\u884c\u7ed3\u675f\u65f6\u8fd9\u4e9b\u5b58\u50a8\u5355\u5143\u81ea\u52a8\u88ab\u91ca\u653e\u3002\u6808\u5185\u5b58\u5206\u914d\u8fd0\u7b97\u5185\u7f6e\u4e8e\u5904\u7406\u5668\u7684\u6307\u4ee4\u96c6\u4e2d，\u6548\u7387\u5f88\u9ad8，\u4f46\u662f\u5206\u914d\u7684\u5185\u5b58\u5bb9\u91cf\u6709\u9650\u3002\u6808\u533a\u4e3b\u8981\u5b58\u653e\u8fd0\u884c\u51fd\u6570\u800c\u5206\u914d\u7684\u5c40\u90e8\u53d8\u91cf\u3001\u51fd\u6570\u53c2\u6570\u3001\u8fd4\u56de\u6570\u636e\u3001\u8fd4\u56de\u5730\u5740\u7b49\u3002<\/li>\n
                  • \u5806\u533a（heap）：\u4e00\u822c\u7531\u7a0b\u5e8f\u5458\u5206\u914d\u91ca\u653e，\u82e5\u7a0b\u5e8f\u5458\u4e0d\u91ca\u653e，\u7a0b\u5e8f\u7ed3\u675f\u65f6\u53ef\u80fd\u7531 OS \u56de\u6536\u3002\u5206\u914d\u65b9\u5f0f\u7c7b\u4f3c\u4e8e\u94fe\u8868\u3002<\/li>\n
                  • \u6570\u636e\u6bb5（\u9759\u6001\u533a）（static）：\u5b58\u653e\u5168\u5c40\u53d8\u91cf\u3001\u9759\u6001\u6570\u636e\u3002\u7a0b\u5e8f\u7ed3\u675f\u540e\u7531\u7cfb\u7edf\u91ca\u653e\u3002<\/li>\n
                  • \u4ee3\u7801\u6bb5：\u5b58\u653e\u51fd\u6570\u4f53（\u7c7b\u6210\u5458\u51fd\u6570\u548c\u5168\u5c40\u51fd\u6570）\u7684\u4e8c\u8fdb\u5236\u4ee3\u7801\u3002<\/li>\n","protected":false},"excerpt":{"rendered":"

                    \u76ee\u5f55
                    \n\u4e3a\u4ec0\u4e48\u8981\u6709\u52a8\u6001\u5185\u5b58\u5206\u914dmalloc \u548c freecalloc \u548c realloc\u5e38\u89c1\u7684\u52a8\u6001\u5185\u5b58\u7684\u9519\u8bef\u52a8\u6001\u5185\u5b58\u7ecf\u5178\u7b14\u8bd5\u9898\u5206\u6790\u67d4\u6027\u6570\u7ec4\u603b\u7ed3 C\/C \u4e2d\u7a0b\u5e8f\u5185\u5b58\u533a\u57df\u5212\u5206
                    \n\u6b63\u6587\u5f00\u59cb
                    \n1. \u4e3a\u4ec0\u4e48\u8981\u6709\u52a8\u6001\u5185\u5b58\u5206\u914d
                    \n\u6211\u4eec\u5df2\u7ecf\u638c\u63e1\u7684\u5185\u5b58\u5f00\u8f9f\u65b9\u5f0f\u6709：
                    \nint val 20; \/\/ \u5728\u6808\u7a7a\u95f4\u4e0a\u5f00\u8f9f\u56db\u4e2a\u5b57\u8282
                    \nchar arr[10] {0}; \/\/ \u5728\u6808\u7a7a\u95f4\u4e0a\u5f00\u8f9f 10 \u4e2a\u5b57\u8282\u7684\u8fde\u7eed\u7a7a\u95f4\u4f46\u662f\u4e0a\u8ff0\u7684\u5f00\u8f9f\u7a7a\u95f4\u7684\u65b9\u5f0f\u6709\u4e24\u4e2a\u7279\u70b9：
                    \n\u7a7a\u95f4\u5f00\u8f9f\u5927<\/p>\n","protected":false},"author":2,"featured_media":115368,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[174,190],"topic":[],"class_list":["post-115370","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-server","tag-c","tag-190"],"yoast_head":"\n\u7b2c21\u8bb2\uff1a\u52a8\u6001\u5185\u5b58\u7ba1\u7406 - \u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.wsisp.com\/helps\/115370.html\" \/>\n<meta property=\"og:locale\" content=\"zh_CN\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"\u7b2c21\u8bb2\uff1a\u52a8\u6001\u5185\u5b58\u7ba1\u7406 - \u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3\" \/>\n<meta property=\"og:description\" content=\"\u76ee\u5f55 \u4e3a\u4ec0\u4e48\u8981\u6709\u52a8\u6001\u5185\u5b58\u5206\u914dmalloc \u548c freecalloc \u548c realloc\u5e38\u89c1\u7684\u52a8\u6001\u5185\u5b58\u7684\u9519\u8bef\u52a8\u6001\u5185\u5b58\u7ecf\u5178\u7b14\u8bd5\u9898\u5206\u6790\u67d4\u6027\u6570\u7ec4\u603b\u7ed3 C\/C \u4e2d\u7a0b\u5e8f\u5185\u5b58\u533a\u57df\u5212\u5206 \u6b63\u6587\u5f00\u59cb 1. \u4e3a\u4ec0\u4e48\u8981\u6709\u52a8\u6001\u5185\u5b58\u5206\u914d \u6211\u4eec\u5df2\u7ecf\u638c\u63e1\u7684\u5185\u5b58\u5f00\u8f9f\u65b9\u5f0f\u6709： int val 20; \/\/ \u5728\u6808\u7a7a\u95f4\u4e0a\u5f00\u8f9f\u56db\u4e2a\u5b57\u8282 char arr[10] {0}; \/\/ \u5728\u6808\u7a7a\u95f4\u4e0a\u5f00\u8f9f 10 \u4e2a\u5b57\u8282\u7684\u8fde\u7eed\u7a7a\u95f4\u4f46\u662f\u4e0a\u8ff0\u7684\u5f00\u8f9f\u7a7a\u95f4\u7684\u65b9\u5f0f\u6709\u4e24\u4e2a\u7279\u70b9： \u7a7a\u95f4\u5f00\u8f9f\u5927\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.wsisp.com\/helps\/115370.html\" \/>\n<meta property=\"og:site_name\" content=\"\u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3\" \/>\n<meta property=\"article:published_time\" content=\"2026-10-11T18:17:11+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/10\/20261011181709-6acbd2a5ce115.png\" \/>\n<meta name=\"author\" content=\"admin\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"\u4f5c\u8005\" \/>\n\t<meta name=\"twitter:data1\" content=\"admin\" \/>\n\t<meta name=\"twitter:label2\" content=\"\u9884\u8ba1\u9605\u8bfb\u65f6\u95f4\" \/>\n\t<meta name=\"twitter:data2\" content=\"4 \u5206\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.wsisp.com\/helps\/115370.html\",\"url\":\"https:\/\/www.wsisp.com\/helps\/115370.html\",\"name\":\"\u7b2c21\u8bb2\uff1a\u52a8\u6001\u5185\u5b58\u7ba1\u7406 - \u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3\",\"isPartOf\":{\"@id\":\"https:\/\/www.wsisp.com\/helps\/#website\"},\"datePublished\":\"2026-10-11T18:17:11+00:00\",\"dateModified\":\"2026-10-11T18:17:11+00:00\",\"author\":{\"@id\":\"https:\/\/www.wsisp.com\/helps\/#\/schema\/person\/358e386c577a3ab51c4493330a20ad41\"},\"breadcrumb\":{\"@id\":\"https:\/\/www.wsisp.com\/helps\/115370.html#breadcrumb\"},\"inLanguage\":\"zh-Hans\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/www.wsisp.com\/helps\/115370.html\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/www.wsisp.com\/helps\/115370.html#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"\u9996\u9875\",\"item\":\"https:\/\/www.wsisp.com\/helps\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"\u7b2c21\u8bb2\uff1a\u52a8\u6001\u5185\u5b58\u7ba1\u7406\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/www.wsisp.com\/helps\/#website\",\"url\":\"https:\/\/www.wsisp.com\/helps\/\",\"name\":\"\u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3\",\"description\":\"\u9999\u6e2f\u670d\u52a1\u5668_\u9999\u6e2f\u4e91\u670d\u52a1\u5668\u8d44\u8baf_\u670d\u52a1\u5668\u5e2e\u52a9\u6587\u6863_\u670d\u52a1\u5668\u6559\u7a0b\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/www.wsisp.com\/helps\/?s={search_term_string}\"},\"query-input\":\"required name=search_term_string\"}],\"inLanguage\":\"zh-Hans\"},{\"@type\":\"Person\",\"@id\":\"https:\/\/www.wsisp.com\/helps\/#\/schema\/person\/358e386c577a3ab51c4493330a20ad41\",\"name\":\"admin\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"zh-Hans\",\"@id\":\"https:\/\/www.wsisp.com\/helps\/#\/schema\/person\/image\/\",\"url\":\"https:\/\/gravatar.wp-china-yes.net\/avatar\/?s=96&d=mystery\",\"contentUrl\":\"https:\/\/gravatar.wp-china-yes.net\/avatar\/?s=96&d=mystery\",\"caption\":\"admin\"},\"sameAs\":[\"http:\/\/wp.wsisp.com\"],\"url\":\"https:\/\/www.wsisp.com\/helps\/author\/admin\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"\u7b2c21\u8bb2\uff1a\u52a8\u6001\u5185\u5b58\u7ba1\u7406 - \u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.wsisp.com\/helps\/115370.html","og_locale":"zh_CN","og_type":"article","og_title":"\u7b2c21\u8bb2\uff1a\u52a8\u6001\u5185\u5b58\u7ba1\u7406 - \u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3","og_description":"\u76ee\u5f55 \u4e3a\u4ec0\u4e48\u8981\u6709\u52a8\u6001\u5185\u5b58\u5206\u914dmalloc \u548c freecalloc \u548c realloc\u5e38\u89c1\u7684\u52a8\u6001\u5185\u5b58\u7684\u9519\u8bef\u52a8\u6001\u5185\u5b58\u7ecf\u5178\u7b14\u8bd5\u9898\u5206\u6790\u67d4\u6027\u6570\u7ec4\u603b\u7ed3 C\/C \u4e2d\u7a0b\u5e8f\u5185\u5b58\u533a\u57df\u5212\u5206 \u6b63\u6587\u5f00\u59cb 1. \u4e3a\u4ec0\u4e48\u8981\u6709\u52a8\u6001\u5185\u5b58\u5206\u914d \u6211\u4eec\u5df2\u7ecf\u638c\u63e1\u7684\u5185\u5b58\u5f00\u8f9f\u65b9\u5f0f\u6709： int val 20; \/\/ \u5728\u6808\u7a7a\u95f4\u4e0a\u5f00\u8f9f\u56db\u4e2a\u5b57\u8282 char arr[10] {0}; \/\/ \u5728\u6808\u7a7a\u95f4\u4e0a\u5f00\u8f9f 10 \u4e2a\u5b57\u8282\u7684\u8fde\u7eed\u7a7a\u95f4\u4f46\u662f\u4e0a\u8ff0\u7684\u5f00\u8f9f\u7a7a\u95f4\u7684\u65b9\u5f0f\u6709\u4e24\u4e2a\u7279\u70b9： \u7a7a\u95f4\u5f00\u8f9f\u5927","og_url":"https:\/\/www.wsisp.com\/helps\/115370.html","og_site_name":"\u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3","article_published_time":"2026-10-11T18:17:11+00:00","og_image":[{"url":"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/10\/20261011181709-6acbd2a5ce115.png"}],"author":"admin","twitter_card":"summary_large_image","twitter_misc":{"\u4f5c\u8005":"admin","\u9884\u8ba1\u9605\u8bfb\u65f6\u95f4":"4 \u5206"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/www.wsisp.com\/helps\/115370.html","url":"https:\/\/www.wsisp.com\/helps\/115370.html","name":"\u7b2c21\u8bb2\uff1a\u52a8\u6001\u5185\u5b58\u7ba1\u7406 - \u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3","isPartOf":{"@id":"https:\/\/www.wsisp.com\/helps\/#website"},"datePublished":"2026-10-11T18:17:11+00:00","dateModified":"2026-10-11T18:17:11+00:00","author":{"@id":"https:\/\/www.wsisp.com\/helps\/#\/schema\/person\/358e386c577a3ab51c4493330a20ad41"},"breadcrumb":{"@id":"https:\/\/www.wsisp.com\/helps\/115370.html#breadcrumb"},"inLanguage":"zh-Hans","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.wsisp.com\/helps\/115370.html"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/www.wsisp.com\/helps\/115370.html#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"\u9996\u9875","item":"https:\/\/www.wsisp.com\/helps"},{"@type":"ListItem","position":2,"name":"\u7b2c21\u8bb2\uff1a\u52a8\u6001\u5185\u5b58\u7ba1\u7406"}]},{"@type":"WebSite","@id":"https:\/\/www.wsisp.com\/helps\/#website","url":"https:\/\/www.wsisp.com\/helps\/","name":"\u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3","description":"\u9999\u6e2f\u670d\u52a1\u5668_\u9999\u6e2f\u4e91\u670d\u52a1\u5668\u8d44\u8baf_\u670d\u52a1\u5668\u5e2e\u52a9\u6587\u6863_\u670d\u52a1\u5668\u6559\u7a0b","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.wsisp.com\/helps\/?s={search_term_string}"},"query-input":"required name=search_term_string"}],"inLanguage":"zh-Hans"},{"@type":"Person","@id":"https:\/\/www.wsisp.com\/helps\/#\/schema\/person\/358e386c577a3ab51c4493330a20ad41","name":"admin","image":{"@type":"ImageObject","inLanguage":"zh-Hans","@id":"https:\/\/www.wsisp.com\/helps\/#\/schema\/person\/image\/","url":"https:\/\/gravatar.wp-china-yes.net\/avatar\/?s=96&d=mystery","contentUrl":"https:\/\/gravatar.wp-china-yes.net\/avatar\/?s=96&d=mystery","caption":"admin"},"sameAs":["http:\/\/wp.wsisp.com"],"url":"https:\/\/www.wsisp.com\/helps\/author\/admin"}]}},"_links":{"self":[{"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/posts\/115370","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/comments?post=115370"}],"version-history":[{"count":0,"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/posts\/115370\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/media\/115368"}],"wp:attachment":[{"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/media?parent=115370"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/categories?post=115370"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/tags?post=115370"},{"taxonomy":"topic","embeddable":true,"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/topic?post=115370"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}