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      std::rewind

      From cppreference.com
      <cpp‎ |io‎ |c
       
       
       
       
      Defined in header<cstdio>
      void rewind(std::FILE* stream);

      Moves the file position indicator to the beginning of the given file stream.

      The function is equivalent tostd::fseek(stream,0,SEEK_SET);, except that end-of-file and error indicators are cleared.

      The function drops any effects from previous calls toungetc.

      Contents

      [edit]Parameters

      stream - file stream to modify

      [edit]Return value

      (none)

      [edit]Example

      Run this code
      #include <array>#include <cstdio> int main(){std::FILE* f=std::fopen("file.txt","w");for(char ch='0'; ch<='9'; ch++)std::fputc(ch, f);std::fclose(f); std::array<char,20> str;std::FILE* f2=std::fopen("file.txt","r"); constunsigned size1=std::fread(str.data(),1, str.size(), f2);std::puts(str.data());std::printf("size1 = %u\n", size1);     std::rewind(f2); constunsigned size2=std::fread(str.data(),1, str.size(), f2);std::puts(str.data());std::printf("size2 = %u", size2); std::fclose(f2);}

      Output:

      0123456789size1 = 100123456789size2 = 10

      [edit]See also

      moves the file position indicator to a specific location in a file
      (function)[edit]
      C documentation forrewind
      Retrieved from "https://en.cppreference.com/mwiki/index.php?title=cpp/io/c/rewind&oldid=145312"

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