PHP iconv from utf-8 to windows-1252 with no special characters

Question

I'm trying to encode a file contents like this:

$f_file = fopen("dreams.txt", "w");  
$string = "Los sueños se cumplen.";    
$string_encoded = iconv( mb_detect_encoding( $string ), 'Windows-1252//TRANSLIT', $string );
fwrite($f_file, $string_encoded);
fclose($f_file);

If $string include a special character such as "ñ" or "á", the file is saved as Windows-1252 encoding but if $string does not include them, the file is encoded as UTF-8. I need the file with Windows-1252 encoding.

What am I doing wrong?

Answer 1

The first 127 characters used in ASCII, ANSI (ISO-8859-1), Windows-1252, and UTF8 are all the same, so it's impossible to tell what "the" encoding is just by looking at a document with only characters from that set: they are all equally applicable.

Modern editors will see this and go "it's 2018 so I'm going to tell you it's UTF8", and they won't even be wrong: until you add those special characters, all these encoding schemes are interchangeable. It's not until you introduce higher bytecode characters that you will have to be explicit about what the encoding is supposed to be again.