使用c计算文件中的行数

Question

我正在尝试创建一个 C 程序来计算文件中的行数。 但它抛出一个错误，如下所示。

请检查并告诉我哪里出了问题

#include <stdio.h>
#include <stdlib.h>

int counter(char *file_name);

int  counter(char *file_name){
char ch;
FILE *fp;
int l=0;
fp = fopen(file_name,"r");

while( ( ch = fgetc(fp) ) != EOF )
{
    if ((ch) == '\n')
    {
        l=l+1;
    }
}
printf("hi there \n");
fclose(fp);
return l;
}

int main() {

    char file_n,*file_name;
    int result;
    printf("Enter File Name: ");
    scanf("%s",&file_n);
    file_name=file_n;
    result=counter(file_name);
    printf("%d",result);
    printf("%s\n",&file_n);
    return 0;
}

PFB执行代码:

subbi@subbi-VirtualBox:~/Desktop$ ls
bar.txt  DWA calssification.py  myp.c  prj1  tes.c  test.c  test.py  tikinter  tkinter_actual  Untitled Document  wctester
subbi@subbi-VirtualBox:~/Desktop$ gcc myp.c 
myp.c: In function ‘main’:
myp.c:30:14: warning: assignment makes pointer from integer without a cast [enabled by default]
     file_name=file_n;
              ^
subbi@subbi-VirtualBox:~/Desktop$ ./a.out 
Enter File Name: bar.txt
Segmentation fault (core dumped)
subbi@subbi-VirtualBox:~/Desktop$ 

Answer 1

ch 必须为int类型；

while( ( ch = fgetc(fp) ) != EOF ) // fails if ch is of type char

参见fgetc() description in (a draft of) the C11 Standard .