Thread: Open file and print user selected number of lines

I am getting compiler errors in my for loop and an illegal break within said for loop...Help?

Errors:

1>c:\users\robert\my programs\assignment 8_exercise 2\source.c(36) : error C2143: syntax error : missing ')' before ';'
1>c:\users\robert\my programs\assignment 8_exercise 2\source.c(36) : error C2059: syntax error : ')'
1>c:\users\robert\my programs\assignment 8_exercise 2\source.c(41) : error C2043: illegal break

Code:

#include <stdio.h>
#include <stdlib.h>
#define LINECOUNT 3;
#define SOURCE_FILE "C:/Users/Robert/Desktop/TestFile1.txt"



int main() 
{
  char c;
  int lineCounter = 0;
  FILE *file; 

  file = fopen(SOURCE_FILE, "r"); 

  if(file==NULL) 
  {
    printf("Error: can't open file.\n");
    return 1;
  }
  else 
  {
    printf("File opened successfully. Contents:\n\n");
    
    for(lineCounter = 0; lineCounter <= LINECOUNT;;)
    {    
      c = fgetc(file);
      if(c = EOF) 
      {
         break;                            
      }
      else if(c = '\n')
      {
         printf("%c", c);
         lineCounter++;
      }
      else 
      {
         printf("%c", c);
      }
    }

    printf("\n\nNow closing file...\n");
    fclose(file);
    return 0;
  }
}

> for(lineCounter = 0; lineCounter <= LINECOUNT;
;; wrong --> ;

you aren't comparing, but assigning.

So the code should read:

Code:

for(lineCounter = 0; lineCounter <= LINECOUNT;)

?

Still doesn't work.

I was hoping this would print the first three lines of text?

Here is my code:

Code:

#include <stdio.h>
#include <stdlib.h>
#define LINECOUNT 3
#define SOURCE_FILE "C:/Users/Robert/Desktop/TestFile1.txt"



int main()
{
  char c;
  int lineCounter = 0;
  FILE *file;

  file = fopen(SOURCE_FILE, "r");

  if(file==NULL)
  {
    printf("Error: can't open file.\n");
    return 1;
  }
  else
  {
    printf("File opened successfully. Contents:\n\n");
   
    for(lineCounter = 0; lineCounter <= LINECOUNT;)
    {   
      c = fgetc(file);
      if(c = EOF)
      {
         break;                           
      }
      else if(c = '\n')
      {
         printf("%c", c);
         lineCounter++;
      }
      else
      {
         printf("%c", c);
      }
    }

    printf("\n\nNow closing file...\n");
    fclose(file);
    return 0;
  }
}

There's a difference between = and ==.

hmm, that would be you aren't comparing but assigning. Guess I was too vague for a newbie.

Originally Posted by Adak

See the suggestions in blue, above. Also, the for loop will fail right off, because lineCount and lineCounter, are both zero, right?

LINECOUNT is a defined constant (3 here).

Originally Posted by Adak

If you want the user to select how many lines of the file are to be printed, then don't you need to get that input from the user?

Surely the user will know to change the constant in the source and recompile? [ducks and runs far away]

I would like the program to wait for user to hit the newline (Enter key) after it prints the first 3 lines of text, if the enter key is hit the program will print three more lines of text, this process will continue for length of document. If any other key is hit before the newline, the program will terminate. Any ideas? Here is my code so far:

Code:

#include <stdio.h>
#include <stdlib.h>
#define LINECOUNT 3
#define SOURCE_FILE "C:/Users/Robert/Desktop/TestFile1.txt"



int main()
{
  char c;
  int lineCounter = 0;
  FILE *file;

  file = fopen(SOURCE_FILE, "r");

  if(file==NULL)
  {
    printf("Error: can't open file.\n");
    return 1;
  }
  else
  {
    printf("File opened successfully. Contents:\n\n");
   
    for(lineCounter = 0; lineCounter < LINECOUNT; )
    {   
      c = fgetc(file);
      if(c == EOF)
      {
         break;                           
      }
      else if(c == '\n')
      {
         printf("%c", c);
         lineCounter++;
      }
      else
      {
         printf("%c", c);
      }
    }
    
    printf("\n\nNow closing file...\n");
    fclose(file);


    
    return 0;
  }
}

Do you know how to get input from the keyboard? Do you want to get input without waiting for the enter key? (That's an FAQ here, if you search on it.)

Originally Posted by tabstop

Do you know how to get input from the keyboard? Do you want to get input without waiting for the enter key? (That's an FAQ here, if you search on it.)

I know how to get input from the keyboard. I do not know how to loop the program so that it prints three lines, waits for the enter key to print three more ect...

Originally Posted by steals10304

I do not know how to loop the program so that it prints three lines, waits for the enter key to print three more ect...

Build a loop, and use the input to determine whether the loop continues.