Setting that to 0 is a bad idea and ill-advised. You won't get any error message if something goes really wrong. Usually (unless you have bad plugins) for Piwigo on PHP 7.3 and earlier it's sufficient to suppress only deprecates

$conf['show_php_errors'] = E_ALL & ~E_DEPRECATED;

but on PHP 7.4 notices want to be suppressed as well.

$conf['show_php_errors'] = E_ALL & ~E_NOTICE & ~E_DEPRECATED;

So how do you configure Piwigo to log all PHP errors to file?
Right, you can't, AFAIK. Most people wouldn't even know how to do that with php.ini or a local .user.ini and crappy hosters might even forbid the latter. So, for all those rather display errors instead of not making them available at all.

However, this (best at the top) in local config logs errors (or however configured) to
piwigo/_data/logs/php-error.log
(unless $conf['data_location'] or $conf['log_dir'] are redefined).

$conf['show_php_errors'] = E_ALL & ~E_DEPRECATED;
if(isset($conf['show_php_errors']) && !empty($conf['show_php_errors']))
{
  // Define subdirectories in case include/config_default.inc.php was not read.
  // Identical (!) to include/config_default.inc.php, including slashes.
  if(!isset($conf['data_location']) || empty($conf['data_location']))
  {
    $conf['data_location'] = '_data/';
  }
  if(!isset($conf['log_dir']) || empty($conf['log_dir']))
  {
    $conf['log_dir'] = '/logs';
  }
  @ini_set('error_log', PHPWG_ROOT_PATH . $conf['data_location'] . $conf['log_dir'] . '/php-error.log');
  @ini_set('log_errors', true);
  @ini_set('error_reporting', $conf['show_php_errors']);
  @ini_set('display_errors', false);
  $conf['show_php_errors_on_frontend'] = false;
  // Set to 0 so the same condition in include/common.inc.php does not override
  // it again to display errors.
  $conf['show_php_errors'] = 0;
}

Note that the error log file has to be cycled manually to not grow forever.

Zentalquabula wrote:

If on, you may accidentally reveal your credentials in SQL statements. It is a REALLY BAD idea.

That might happen if everything is completely rotten, yes.

If you can set up a server, you can also set up error logging. It is on per default in 7.4.

My impression is that most users wouldn't know either one nor the other.

If the host doesn't allow it, switch host.

Agreed, still, many wouldn't.

Anyway, I agree that error display is to be avoided and logged instead. I posted working Piwigo config code for how to switch from display_errors to log_errors if PHP is setup differently (or in any case for local to Piwigo logging).

Sorry - I missed adding the php directives at the start and end of the file

This worked for me:
root dir

/home/mysite/myhtml/.htaccess

following two lines:

php_flag error_reporting On
php_flag display_errors Off

linux ubuntu 18.04 & 20.04
php8.1 (as @kenk mentioned the code is a bit messy. It shows lots of errors on switch to php 8.x)
apache2
#### edit #####
I have to qualify the above. The only errors I was seeing were in the osm plugin. OpenStreetMap.

Last edited by grantiago (2023-01-16 20:48:17)