PHP系统命令函数使用分析

复制代码 代码如下:

  function execute($cmd) {

  $res = '';

  if ($cmd) {

  if(function_exists('system')) {

  @ob_start();

  @system($cmd);

  $res = @ob_get_contents();

  @ob_end_clean();

  } elseif(function_exists('passthru')) {

  @ob_start();

  @passthru($cmd);

  $res = @ob_get_contents();

  @ob_end_clean();

  } elseif(function_exists('shell_exec')) {

  $res = @shell_exec($cmd);

  } elseif(function_exists('exec')) {

  @exec($cmd,$res);

  $res = join(“\n",$res);

  } elseif(@is_resource($f = @popen($cmd,"r"))) {

  $res = '';

  while(!@feof($f)) {

  $res .= @fread($f,1024);

  }

  @pclose($f);

  }

  }

  return $res;

  }