这不是放一个文件进去，然后读取第一个文件，复制到另一个文件吗，为什没有…

#include<stdio.h> 
#include<ctype.h> 
void main() {

    FILE* p1, * p2; char ch;

    p1 = fopen("d1.dat", "r");

    p2 = fopen("d2.dat", "w");

    while (feof(p1) == 0)

    {

        ch = fgetc(p1);
        if (isalpha(ch))
            fputc(ch, p2);
    }
    fclose(p1); fclose(p2);
}

d1.dat里面有字符吗

供参考：

#include<stdio.h>
#include<ctype.h>
int main()
{
    FILE *fp1,*fp2;
    char ch;
    fp1=fopen("d1.txt","r");
    if(fp1 == NULL){
        printf("open file fail!\n");
    }
    else{
        fp2=fopen("d2.txt","w");
        if(fp2 == NULL){
           printf("open file fail!\n");
        }
        else{
           while(feof(fp1)==0)
           {
               ch = fgetc(fp1);
               if(isalpha(ch))
                  fputc(ch,fp2);
           }
           fclose(fp2);
        }
        fclose(fp1);
    }
    return 0;
}