php 异步执行脚本程序代码

//main.php
<?php
    $cmd = 'nohup php ./sub.php >./tmp.log  &';
    exec($cmd);
    $cmd = 'nohup php ./sub1.php >/dev/null  &';
    exec($cmd);
?>

//sub1.php sub2.php
<?php
    sleep(100000);
?>

header("Pragma: public");
header("Expires: 0");
header("Cache-Control:must-revalidate, post-check=0, pre-check=0");
header("Content-Type:application/force-download");
header("Content-Type:application/vnd.ms-execl");
header("Content-Type:application/octet-stream");
header("Content-Type:application/download");
header('Content-Disposition:attachment;filename="excel.xls"');
header("Content-Transfer-Encoding:binary");
$objWriter->save('php://output');

 if(empty($id)) $id=1;
    print $id; // 得到 1

    if(!isset($id)) $id=1;
 print $id; //得到 0

测试代码：

$sep = "<br />";

echo 'test undeclared var empty : ';
var_dump(empty($var)); // TRUE
echo $sep . 'test undeclared var isset : ';
var_dump(isset($var)); // FALSE

$var;
echo $sep . 'test declared var but no set value empty : ';
var_dump(empty($var)); // TRUE
echo $sep . 'test declared var but no set value isset : ';
var_dump(isset($var)); // FALSE, 变量申明未赋值，默认值为NULL

$var = NULL;
echo $sep . 'test declared var and set value NULL empty : ';
var_dump(empty($var)); // TRUE
echo $sep . 'test declared var and set value NULL isset : ';
var_dump(isset($var)); // FALSE, 变量申明赋值为NULL

$var1 = ''; $var2 = '0'; $var3 = 0; $var4 = FALSE; $var5 = array();

echo $sep . 'test '' empty : ';
var_dump(empty($var1)); // TRUE
echo $sep . 'test '0' empty : ';
var_dump(empty($var2)); // TRUE
echo $sep . 'test 0 empty : ';
var_dump(empty($var3)); // TRUE
echo $sep . 'test FALSE empty : ';
var_dump(empty($var4)); // TRUE
echo $sep . 'test array() empty : ';
var_dump(empty($var5)); // TRUE
echo $sep . 'test '', '0', 0, FALSE, array() isset : ';
var_dump(isset($var1, $var2, $var3, $var4, $var5)); // TRUE,  变量申明并赋值为空字符串输出的结果为：

test undeclared var empty : bool(true)
test undeclared var isset : bool(false)
test declared var but no set value empty : bool(true)
test declared var but no set value isset : bool(false)
test declared var and set value NULL empty : bool(true)
test declared var and set value NULL isset : bool(false)
test '' empty : bool(true)
test '0' empty : bool(true)
test 0 empty : bool(true)
test FALSE empty : bool(true)
test array() empty : bool(true)
test '', '0', 0, FALSE, array() isset : bool(true)

function mkdirs($dir){
    if(!is_dir($dir)){
        if(!mkdirs(dirname($dir))){
            return FALSE;
        }

        if(!mkdir($dir, 0777)){
            return FALSE;
        }
    }

    return TRUE;
}

  $path="/aa/bb/cc/cd"; //要创建的目录
   $mode=0755; //创建目录的模式
   createdir($path,$mode);//测试

<?php
/*
*mkdir($dir,$mode)
*PHP 递归创建目录
*/
function mkdirs($dir, $mode = 0777)
{
    if (is_dir($dir) || @mkdir($dir, $mode)){
        return true;
    }
    if (!mkdirs(dirname($dir), $mode)){
        return false;
    }
    return @mkdir($dir, $mode);
}

function mkdirs($dir, $mode = 0777)
{
    $dirArray = explode("/",$dir);
    $dirArray = array_filter($dirArray);
  
    $created = "";
    foreach($dirArray as $key => $value){
        if(!empty($created)){
            $created .= "/".$value;
            if(!is_dir($created)){
                mkdir($created,$mode);
            }
        }else{
            if(!is_dir($value)){
                mkdir($value,$mode);
            }
            $created .= $value;
        }
    }
}
?>
//代码应用实例
$path="abc/ff/ss/";
mkdirs($path,$mode = 0777);

$context = stream_context_create(array(
     'http' => array(
      'timeout' => 3000 //超时时间，单位为秒
     )
)); 
// Fetch the URL's contents
$contents = file_get_contents('http://www.111cn.net', 0, $context);

$opts = array(
'http'=>array(
'method'=>"GET",
'timeout'=>60,
)
);
$context = stream_context_create($opts);
$html =file_get_contents('http://www.111cn.net', false, $context);

$cnt=0; 

while($cnt < 3 && ($str=@file_get_contents('http...'))===FALSE) $cnt++;

function Post($url, $post = null)
{
$context = array();

if (is_array($post))
{
ksort($post);

$context['http'] = array
(

'timeout'=>60,
'method' => 'POST',
'content' => http_build_query($post, '', '&'),
);
}

return file_get_contents($url, false, stream_context_create($context));
}

$data = array
(
'name' => 'test',
'email' => 'test@gmail.com',
'submit' => 'submit',
);

echo Post('http://www.111cn.net', $data);