Question

Can someone please explain why this code:

$str = "StackOverflow"; 
echo $str . " - ";

$strCompressed = gzcompress($str);
//echo $strCompressed . " - ";

$strUncompressed = gzuncompress($strCompressed);
echo $strUncompressed . " - ";

gives the expected output of: StackOverflow - StackOverflow -

but this code (writing and reading from file):

$str = "StackOverflow";
$strCompressed = gzcompress($str);

$file = "test.cache";
$fp = fopen($file, "w");
fwrite($fp, $strCompressed);
fclose($fp);

$strCompressed = readfile($file);
echo gzuncompress($strCompressed);

does not produce the wated output of StackOverflow?

Also, I’m wondering, if I uncoment the commented line of code in the first example (//echo $strCompressed . " - ";) the script will output something like this: StackOverflow - xś.ILÎö/K-JËÉ/, so as you can see without the second StackOverflow - as with that line comented out. Any insight is appreciated.

Answer 1

Try this:

$strCompressed = file_get_contents($file);
echo gzuncompress($strCompressed);

readfile doesn’t return the file’s contents but outputs them