rewind

函数名: rewind()

功 能: 将文件内部的位置指针重新指向一个流（数据流/文件）的开头

注意：不是文件指针而是文件内部的位置指针，随着对文件的读写文件的位置指针（指向当前读写字节）向后移动。而文件指针是指向整个文件，如果不重新赋值文件指针不会改变。

rewind函数作用等同于 (void)fseek(stream, 0L, SEEK_SET);[1] 

用 法: void rewind(FILE *stream);

头文件： stdio.h

返回值：无

#include <stdio.h>

#include <dir.h>

int main(void)

{

FILE *fp;

char fname[10] = "TXXXXXX", *newname, first;

newname = mktemp(fname);

fp = fopen(newname,"w+");

if(NULL==fp)

return 1;

fprintf(fp,"abcdefghijklmnopqrstuvwxyz");

rewind(fp);

fscanf(fp,"%c",&first);

printf("The first character is: %c\n",first);

fclose(fp);

remove(newname);

return 0;

}

A statement such as

rewind( cfptr );

causes a program's file position--which indicates the number of the next byte in the file to be read or written-- to be repositioned to the beginnning of the file pointed to by cfptr.