Thread: Keep reading lines in a file

Check fscanf for EOF. Also remember that reading strings with scanf is unsafe unless you properly use format specifiers which you don't. Recommend you use fgets instead. Think about that.
And fix your indentation!

ya,i commented out that part because i didn't need it ya im rushing this so its not indented properly.

Anyways ill try the EOF part.

IT doesn't matter if you rush or not - it's NOT an excuse for poor indenting.
You indent as you type and NOT the other way around.
Poor indenting creates more bugs than it solves so always indent when you first write your code, and not afterwards or as an afterthought.

ok ill do it

anyways, i used the feof and it works thanks alot really helped

Beware that feof only returns true AFTER you've attempted to read beyond the file. What does this mean? If you read something from the file, beyond the the file, feof will be true, but then you do another read (because you use feof as a loop condition), the second read will fail miserably.
See the FAQ for more info on that.

so if i was to read the file again it will fail? What about if i used rewind?

Code:

while (! feof(my_file) )
{
	fread(my_buf, my_size, 1, my_file);
	fread(my_buf, my_size, 1, my_file);
}

The problem with this code is that if the first fread fails, then you may get unpredicted results with the second read, since you're expecting the code to continuously succeed until feof returns false at which time you abort.
See the FAQ for more on this.
(Rule: using feof as a condition for the loop is bad; consider using a read as a condition since it will fail if you try to read beyond the file.)

ok so i should modify it to this?

Code:

  while (fgets(buf, sizeof(buf), fp) != NULL)
  {
    printf ("Line %4d: %s", i, buf);
    i++;
  }

also, i wanna pass a array into a function but when it goes into the fuction the array equals zero

Code:

#include <stdio.h>
   double cGross(double hours[], double emprate) { 
       printf("%d\n", hours[1]); <<displays zero
       if (emprate = 1){
                   emprate = emprate * hours[1];
                   }
       return emprate;
   }
   
   main() {
      FILE *fp;
      FILE *empinfo;
      int line[9], i = 0, k = 0;
      
      /*double empnum = 0;*/
      double emphours,  hours[9], gross = 0, emprate;
      char first[256], last[256], empnum[256];
      /*Loads the hourly rates in an array*/
      fp = fopen("payrates.dat", "r");
      if (fp == NULL)
         printf("Cannot open %s\n", fp);
         
      else {  
         for (i = 0; i < 10; i++) {   
           
         fscanf(fp, "%lf\n", &hours[i]);
         printf("%.2lf\n", hours[i]);
         }
         fclose(fp);
      }
      /*end of hourly rates*/
      
      
      empinfo = fopen("employees.dat", "r");
      if (fp == NULL) {
         printf("Cannot open %s\n", fp);
         }
      else {
           /*printf("What is the 4 digit employee number: ");
           scanf("%s", first);*/
           do {
               
               fscanf(empinfo, "%[^:]:%[^:]:%[^:]:%d:%lf\n", empnum, last, first, &emprate, &emphours);
               gross = cGross(hours, emprate);
               printf("%d ", gross);
               printf("%s ", empnum);
               printf("%s ", first);
               printf("%s ", last);
               printf("%5.d ", emprate);
               printf("%5.2lf\n", emphours);
           } while (! feof(empinfo));
           fclose(empinfo);
           }
   }

The loop is fine.
Why hours[1] is 0, I don't know. I don't have the file contents so I can't debug, but I don't see anything wrong with the code.

And now for comments:

Code:

int main() {

main should return int! Thought I told you...

Code:

int line[9]

Never used anywhere so you can remove it.

ya there was a couple stuff i forgot to do so end of main i should put return 0;

Ya, you should do that. Compilers, nowadays...

ok fixed the stuff you suggested, but about the hours array the values are saved because when i do a loop of the hours array it displays its contents but when sent to the functions cGross it displays 0 for all, somethings is probably not passing

Syntax is correct. I tried initializing the array with values and calling the function to display them later and it worked fine, so I would assume something else is happening, but I can't tested without the contents of the files.
You don't use a debugger, do you?

if you have the time for it

Code:

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