统计网站访问IP以及在线的人数，推荐使用成熟的统计程序来完成，下面这篇适合局域网或小型dome使用，实现简单小巧的php统计在线人数和IP功能。
首先我们需要开启php依赖putenv()函数模块，找到php.ini文件，搜索putenv关键字，删除即可。
如果你使用的宝塔面板环境，点击左侧软件管理，找到php，然后设置->禁用函数。
isable_functions = passthru,exec,system,putenv,chroot,chgrp,chown,shell_exec,popen,proc_open,pcntl_exec,ini_alter,ini_restore,dl,openlog,syslog,readlink,symlink,popepassthru,pcntl_alarm,pcntl_fork,pcntl_waitpid,pcntl_wait,pcntl_wifexited,pcntl_wifstopped,pcntl_wifsignaled,pcntl_wifcontinued,pcntl_wexitstatus,pcntl_wtermsig,pcntl_wstopsig,pcntl_signal,pcntl_signal_dispatch,pcntl_get_last_error,pcntl_strerror,pcntl_sigprocmask,pcntl_sigwaitinfo,pcntl_sigtimedwait,pcntl_exec,pcntl_getpriority,pcntl_setpriority,imap_open,apache_setenv
删除putenv，然后重启php即可。
下面是PHP统计函数代码
在count.php同目录下创建文件：count,temp,online。新建文本文档count.txt，去掉扩展名即为count了；
linux系统中请设置文件属性为：777。
文件count.php代码，用到了PHP函数--explode、isset、empty及sprintf等:
<?php
$file = "count"; // 记数文件名称
$startno = "1000"; // 起始数值
$tempfile = "temp";
$t_now = time();
$t_array = getdate($t_now);
$day = $t_array['mday'];
$mon = $t_array['mon'];
$year = $t_array['year'];
if (file_exists("$file")) {
$count_info=file("$file");
$c_info = explode(",", $count_info[0]);
$total_c=$c_info[0];
$yesterday_c=$c_info[1];
$today_c=$c_info[2];
$lastday=$c_info[3];
} else {
$total_c="$startno";
$yesterday_c="0";
$today_c="0";
$lastday="0";
}
if ( !isset($HTTP_COOKIE_VARS["countcookie"]) || $HTTP_COOKIE_VARS["countcookie"] != $day) {
$your_c=1;
$lockfile=fopen("temp","a");
flock($lockfile,3);
putenv('TZ=JST-9');
$t_array2 = getdate($t_now-24*3600);
$day2=$t_array2['mday'];
$mon2=$t_array2['mon'];
$year2=$t_array2['year'];
$today = "$year-$mon-$day";
$yesterday = "$year2-$mon2-$day2";
if ($today != $lastday) {
if ($yesterday != $lastday) $yesterday_c = "0";
else $yesterday_c = $today_c;
$today_c = 0;
$lastday = $today;
}
$total_c++;
$today_c++;
$total_c = sprintf("%06d", $total_c);
$today_c = sprintf("%06d", $today_c);
$yesterday_c = sprintf("%06d", $yesterday_c);
setcookie("countcookie","$day",$t_now+43200);
$fp=fopen("$file","w");
fputs($fp, "$total_c,$yesterday_c,$today_c,$lastday");
fclose($fp);
fclose($lockfile);
}
if ( empty( $your_c ) ) $your_c = 1;
setcookie("yourcount",$your_c+1,$t_now+43200);
$your_c = sprintf("%06d", $your_c);
//////////////////////////开始统计在线
$filename="online";
$onlinetime=600; //同一IP在线时间，单位：秒
$online_id=file($filename);
$total_online=count($online_id);
$ip=getenv("REMOTE_ADDR");
$nowtime=time();
for($i=0;$i<$total_online;$i++){
$oldip=explode("||",$online_id[$i]);
$hasonlinetime=$nowtime-$oldip[0];
if($hasonlinetime<$onlinetime and $ip!=$oldip[1]) $nowonline[]=$online_id[$i];
}
$nowonline[]=$nowtime."||".$ip."||";
$total_online=count($nowonline);
$fp=fopen($filename,"w");
rewind($fp);
for($i=0;$i<$total_online;$i++){
fputs($fp,$nowonline[$i]);
fputs($fp,"n");
}
fclose($fp);
if($total_online==0)$total_online=1;
$total_online = sprintf("%06d", $total_online);
///////////////////////////////////////////////////////
echo "document.write("·总IP访问:".$total_c."");";
echo "document.write("<br>");";
echo "document.write("·昨日访问:".$yesterday_c."");";
echo "document.write("<br>");";
echo "document.write("今日IP:".$today_c."");";
echo "document.write(" ");";
echo "document.write("·您 访 问:".$your_c."");";
echo "document.write("<br>");";
echo "document.write("当前在线:".$total_online."");";
exit;
?>