PHP直接java错误

$cmdStr = '/soft/java_env/jdk-15.0.1/bin/java -version 2>&1 &'; //1
$cmdStr_err = "/soft/java_env/jdk-15.0.1/bin/java -version";//2
exec($cmdStr,$result);
var_dump($result);

2 result为空 1可以显示出内容

原因转自 https://blog.csdn.net/u011630575/article/details/52151995