That is strange. On my machine, I get output like:

ungot 'l' 21037 => 21036

So ungetc is broken on the Mac?

[espeak-ng:master] New Comment on Issue #674 Build fails on MacOS Catalina
By BenTalagan:

I'm trying to narrow the problem ; could you try to compile and launch this small program on your machine ?

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

FILE* f_in = NULL;

static unsigned int get_char()
{
	unsigned int c;
	c = fgetc(f_in);
  printf("Got '%c'\n", c);
	return c;
}

static void unget_char(unsigned int c)
{   
	ungetc(c, f_in);
  printf("Ungot '%c'\n", c);
}

int main(int argc, char** argv) {

  f_in = fopen("testfile","rb");

  if(!f_in)
  {
    printf("Failed to open test file \n");
    return -1;
  }

  int triggered = 0;
  while(!feof(f_in))
  {
    int c = get_char();
    if( c== '4' && !triggered) {
      unget_char(' ');
      triggered = 1;

      int cpos = ftell(f_in);
      printf("FTELL : %d\n",cpos);
    }
  }

  fclose(f_in);
  return 0;
}

The behaviour of that program is strange to me, it has the 'jump' effect :

Got '1'
Got '
'
Got '2'
Got '
'
Got '3'
Got '
'
Got '4'
Ungot ' '
FTELL : 14
Got '8'
Got '?'

[espeak-ng:master] New Comment on Issue #674 Build fails on MacOS Catalina
By BenTalagan:

This is the test file "testfile" that goes alongside the program :

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