我如何遍历传递给函数的char数组并返回char数

Question

#include "Definition.h"
#include <stdio.h>
#include "ExternalVar.h"
#include <stdlib.h>
#include <string.h>

extern int Readline(),CountWord(),CountsUpdate();


char Line[MaxLine];  /* one line from the file */


int NChars = 0,  /* number of characters seen so far */
    NWords = 0,  /* number of words seen so far */
    NLines = 0,  /* number of lines seen so far */
    LineLength;  /* length of the current line */ 

int wc = 0,
    lc = 0,
    cc = 0,
    tc = 0;


int i;

main(int argc, char *argv[])  
{
    FILE *fp;
    fp= fopen(argv[1],"r");
    if (fp) 
    {
        while (i=fscanf(fp,"%s",Line)!=EOF)
        ///printf("%s \n",Line);
        cc=Readline(Line);
        printf("%d \n",cc);
        fclose(fp);


    }
    return 0;  
}

This is my main function I am passing the char array Line[] to the function Readline(Line) and I want it to return the number of chars in the array.

Here is the function Readline.c . No matter which text file I use as the argument I keep getting 84 as the returning value. Not sure what I am doing wrong or right since I am new to C programming. Please help.

#include "Definition.h"
#include "ExternalVar.h"
#include <stdio.h>



int Readline(char *Line)
{   
int i;


for (i = 0; Line[i] == '\n' ; i++)
{

return i;
}
}

Output is as folllows

taj@taj:~/Desktop/2014_Summer_CIS5027_Asg2$ gcc Main.c Readline.c taj@taj:~/Desktop/2014_Summer_CIS5027_Asg2$ ./a.out b.txt

84

Answer 1

You have few problems:

1) You probably want to check until you hit \\n . So the condition should really be:

for (i = 0; Line[i] != '\n' ; i++)

2) Your input may not contain \\n . So you should also check whether you have reached the end of the string:

for (i = 0; Line[i] && Line[i] != '\n' ; i++)

3) What if the first character is \\n in Line ? It won't enter the loop at all and you are not returning anything in that case. So you should initialize i=0 and return it. You could rewrite the function as:

int Readline(char *Line)
{   
int i = 0;

  for (i = 0; Line[i] && Line[i] != '\n' ; i++)
  {
  ;
  }

return i;
}

4) fscanf() with %s format doesn't read \\n even if your input file contains it. You probably want to use fgets() to read which does read the \\n chars:

while (fgets(Line, sizeof Line, fp)) {
  ...
}

5) main() function should return an int : int main(int argc, char *argv[]) {... }

Answer 2

int Readline(char *Line){
    int i;
    for (i = 0; Line[i] != '\0' ; i++)//newline is not included in the Line. Because read by fscanf(fp,"%s",Line)
        ;

    return i;
}