std::rewind - cppreference.com (original) (raw)

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

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

The function drops any effects from previous calls to ungetc.

[edit] Parameters

stream - file stream to modify

[edit] Return value

(none)

[edit] Example

#include #include   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");   const unsigned size1 = std::fread(str.data(), 1, str.size(), f2); std::puts(str.data()); std::printf("size1 = %u\n", size1);   std::rewind(f2);   const unsigned size2 = std::fread(str.data(), 1, str.size(), f2); std::puts(str.data()); std::printf("size2 = %u", size2);   std::fclose(f2); }

Output:

0123456789 size1 = 10 0123456789 size2 = 10

[edit] See also