Difference between revisions of "cpp/io/c/rewind"
From cppreference.com
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| − | Moves the file position indicator to the beginning of the given file stream | + | Moves the file position indicator to the beginning of the given file stream. |
| + | |||
| + | The function is equivalent to {{cc|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 {{lc|ungetc}}. | ||
===Parameters=== | ===Parameters=== | ||
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{{example| | {{example| | ||
| code= | | code= | ||
| + | #include <cstdio> | ||
| + | |||
| + | int main() | ||
| + | { | ||
| + | std::FILE *f; | ||
| + | char ch; | ||
| + | char str[20]; | ||
| + | |||
| + | f = std::fopen("file.txt", "w"); | ||
| + | for (ch = '0'; ch <= '9'; ch++) { | ||
| + | std::fputc(ch, f); | ||
| + | } | ||
| + | std::fclose(f); | ||
| + | |||
| + | std::fopen("file.txt", "r"); | ||
| + | std::fread(str, 1, 10, f); | ||
| + | std::puts(str); | ||
| + | |||
| + | std::rewind(f); | ||
| + | std::fread(str, 1, 10, f); | ||
| + | std::puts(str); | ||
| + | std::fclose(f); | ||
| + | } | ||
| output= | | output= | ||
}} | }} | ||
Revision as of 05:55, 21 October 2013
| Defined in header <cstdio>
|
||
| void rewind( std::FILE* stream ); |
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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.
Contents |
Parameters
| stream | - | file stream to modify |
Return value
(none)
Example
Run this code
#include <cstdio> int main() { std::FILE *f; char ch; char str[20]; f = std::fopen("file.txt", "w"); for (ch = '0'; ch <= '9'; ch++) { std::fputc(ch, f); } std::fclose(f); std::fopen("file.txt", "r"); std::fread(str, 1, 10, f); std::puts(str); std::rewind(f); std::fread(str, 1, 10, f); std::puts(str); std::fclose(f); }
See also
| moves the file position indicator to a specific location in a file (function) | |
| C documentation for rewind
| |
