宝塔面板更新composer

宝塔面板安装成功，执行

composer create-project topthink/think tp 

　命令时，提示下面错误。

Warning: This development build of composer is over 60 days old. It is recommended to update it by running "/usr/bin/composer self-update" to get the latest version.
Creating a "topthink/think" project at "./pm"

composer update

　命令同样提示错误

Warning: This development build of composer is over 60 days old. It is recommended to update it by running "/usr/bin/composer self-update" to get the latest version.
Composer could not find a composer.json file in /www/wwwroot
To initialize a project, please create a composer.json file as described in the https://getcomposer.org/ "Getting Started" section

执行 

 /usr/bin/composer self-update

升级成功。