Warning: Undefined array key "HTTP_REFERER" in /renewpeople/www/gnuboard4/bbs/visit_insert.inc.php on line 13

Deprecated: mysqli_real_escape_string(): Passing null to parameter #2 ($string) of type string is deprecated in /renewpeople/www/gnuboard4/bbs/visit_insert.inc.php on line 13

Fatal error: Uncaught TypeError: mysqli_query(): Argument #1 ($mysql) must be of type mysqli, string given in /renewpeople/www/gnuboard4/lib/common.lib.php:1142
Stack trace:
#0 /renewpeople/www/gnuboard4/lib/common.lib.php(1142): mysqli_query(' insert g4_visi...', false)
#1 /renewpeople/www/gnuboard4/bbs/visit_insert.inc.php(18): sql_query(' insert g4_visi...', false)
#2 /renewpeople/www/gnuboard4/common.php(519): include_once('/renewpeople/ww...')
#3 /renewpeople/www/gnuboard4/bbs/_common.php(3): include_once('/renewpeople/ww...')
#4 /renewpeople/www/gnuboard4/bbs/board.php(2): include_once('/renewpeople/ww...')
#5 {main}
  thrown in /renewpeople/www/gnuboard4/lib/common.lib.php on line 1142