Undefined Variable 500 Error

I appreciate your interest and response. thank you.

but as in the video.

If ci3 log is activated, it logs regardless of the environment.

but if I do the error_logs(0) you told me, even if ci4 log is on. Even if the log level is 9, it does not log.


[Video: https://www.youtube.com/watch?v=eoKgtHeXohM]

The behavior of CI3 seems to be different from CI4.

CI4 only logs errors with the error level set by error_reporting(). Ignored errors are not logged. 
Also, an error that is not ignored will stop processing.

CI3 behaves differently. 
Only errors that correspond to E_ERROR | E_PARSE | E_COMPILE_ERROR | E_CORE_ERROR | E_USER_ERROR will stop processing, regardless of the error level set in error_reporting().
Ignored errors are not logged, but other errors are logged.

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Which one do you think is right?
In Ci3, the project continues to run and logs these errors, you can debug by examining the logs.

In ci4, this error stops the script with a 500 error. and logs it. you can debug, but since that process has stopped, you have to run that process or service again with all its parameters as if you were the same user.

In ci4 you can set error_reporting to 0 and the script will continue to run, but it will not give you any idea to debug because it does not log any errors.

Translated with DeepL.com (free version)

I don't recommend to set error_reporting to 0. It means to ignore all errors.

CI4's behavior is severe, but I think it is right and simple.
However, if your code is buggy and impractical to fix, you will have no choice but to customize CI4's behavior if you use CI4.

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