Thread: getw/putw problem

I tried to write/read a line of intergers(like 12345) to a file using getw, but I don't know how to stop the input loop, like this:

Code:

#include<stdio.h> 
int main(void)
{ 
  FILE *f1,*f2,*f3; 
  int number; 
  printf("Content of the data file\n"); 
  f1=fopen("data","w"); 

  while((number=getw(stdin))!='\n')
   putw(number,f1);

  fclose(f1); 
  
  f1=fopen("data","r"); 
  f2=fopen("odd","w"); 
  f3=fopen("even","w"); 
  
  while((number=getw(f1))!=EOF)/* Read from data file*/ 
  { 
  if(number%2==0) 
   putw(number,f3);/*Write to even file*/ 
  else 
   putw(number,f2);/*write to odd file*/ 
  } 
  
  fclose(f1); 
  fclose(f2); 
  fclose(f3); 
  f2=fopen("odd","r"); 
  f3=fopen("even","r"); 
  
  printf("\n\nContent of the odd file\n\n"); 
  while((number=getw(f2))!=EOF) 
   printf("%d%d",number); 
   
  printf("\n\nContents of the even file"); 
  while((number=getw(f3))!=EOF) 
   printf("%d",number); 
   
  fclose(f2); 
  fclose(f3); 
  getch();
  return 0;
}

Please help me consider it

If getw reads a number (a wild guess based on typing "man getw" into Google), then why would you expect it to ever be \n? According to the man pages I'm seeing (assuming we're even talking about the same thing), getw returns EOF on error.

I guess you need to decide, how you want the user to stop typing numbers.

Yeah, that's what I'm considering. I want user to stop typing numbers by pressing enter(suggest some other "smooth" ways?) but getw is only used with intergers

Originally Posted by matsp

Two simple variants:
1. Use a "sentry value", e.g. enter 0, -1, -99999999 or some other value that is not in the valid range that can be used as "this is the end of input".
2. Read the value as a string, and then convert using strtol() or a similar function.

--
Mats

1.I've changed '\n' into -1 and it doesn't help. dunno
2.I just want to see how getw works and don't want to resort to string usage here

@Philip:

...or simply ask the user how many numbers he wants to enter and then ask for a number that many times.

Asking for a number is ok but what I want to know is how getw stops (as scanf stops at the first space/tab/newline)