文件读写操作

编程完成读出文件中的内容，反序输出到屏幕中

#include < stdio.h >
#include < stdlib.h >
#include < conio.h >
#define  N 5000

void  main()
{
    FILE  * sfp;
     int  i;
     char  buf[N];
     if ((sfp = fopen( " c:\\datafile.txt " , " r " )) == NULL)
    {
        printf( " Source file cannot be opened!\n " );
        exit( 1 );
    }
    i = 0 ;
     while ( ! feof(sfp))
    {
        buf[i ++ ] = fgetc(sfp);
         if (i >= N)
        {
            printf( " buffer not enough! " );
            exit( 1 );
        }
    }
     while ( -- i >= 0 )
        fputc(buf[i],stdout);
    fclose(sfp);
    getch();
}