Why did you fail to use the swoole_process callback class method in laravel's custom command line program?

help me: I use swoole_process in laravel"s artisan command program. When you create a process and use [$this, "functionName"] as a callback function, you can see why the execution failed. See the error in the picture that this method does not exist. Swoole"s official demo is all used as a callback function in the form of closures, but it can be run by using class methods as callbacks, and colleagues" demo can run normally.
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Aug.27,2021
The reason for

is found, because my callback function is accidentally written as protected, which will cause the callback to fail.

MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1b3a6f2-2c21a.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b3a6f2-2c21a.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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