How could I improve my code for printing to a text file in C?

Question

I'm working with the open-source thermal simulator HotSpot 6.0, I seek to extract the dimensional parameters -x and -y onto a text file to use for a new thermal modeling tool.

I've tried terminal printing x and y locations:

fprintf(stdout, "Location in x: %u\n", i1);
fprintf(stdout, "Location in y: %u\n", j1);

The above code prints lines of i1 and j1 numbers, but I would like to have them saved to a text file. The code below is my attempt at printing to a text file.

FILE *fptr;
fptr = fopen("Dimensions.txt","w");
fprintf(fptr,"%u\t %u\t",i1,j1);
fclose(fptr);

The output of the code above prints only one line of code. I would like to know why this is to fix it.

Remove the newline character and replace with spaces/tabs? You might also want to look at the width specifier for the format strings. — Eugene Sh., Jul 16 '19 at 15:58
And perhaps a single `fprintf` with a format string having two specifiers? — Tanveer Badar, Jul 16 '19 at 16:01
That did make them separated by column, but it only creates one line of data compared to my fprintf(stdout) code — Jhonatan Palacios, Jul 16 '19 at 16:02
I don't understand your question. How many lines do you expect? And why? — Eugene Sh., Jul 16 '19 at 16:03
Could you edit the question to add the desired output and what you're getting? Because it's getting kind of confusing. — DeiDei, Jul 16 '19 at 16:03
Your edit have just invalidated the previous comments, but did not make it any clearer. You are printing one line and asking why it is printing one line. — Eugene Sh., Jul 16 '19 at 16:10

Bo R · Answer 1 · 2019-07-16T20:40:55.610

0

Here is an improvement suggestion:

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

int main(void) {
  unsigned i1 = 101;
  unsigned j1 = 202;

  FILE *fptr = fopen("Dimensions.txt", "w");
  if (fptr == NULL) {
    fprintf(stderr, "Can not open/create file\n");
    exit(EXIT_FAILURE);
  }
  fprintf(fptr, "%u %u\n", i1, j1);
  fclose(fptr);
  return EXIT_SUCCESS;
}

edited Jul 16 '19 at 20:40

answered Jul 16 '19 at 16:12

Bo R

2,334
1
9
17

What does it improve? – Eugene Sh. Jul 16 '19 at 16:19
1

Er, why be cute with the comma operator in that error check and not a more usual `if (fptr == NULL) { fprintf(stderr, "Can not open/create file\n"); exit(EXIT_FAILURE); }`? – Shawn Jul 16 '19 at 16:38
@EugeneSh. The question was different when I answered it (it used two `printf`). Now I'm a bit confused as to what the question asker wants. – Bo R Jul 16 '19 at 20:38
@Shawn It was a bit hasty to my local formatter to not use so many lines. I'll adjust. – Bo R Jul 16 '19 at 20:39

How could I improve my code for printing to a text file in C?

1 Answers1