how to propagate errors?

[TheJuice]

Hi,
I'd like to know of the best way to catch all errors and warning I generated in my functions, to print them when all functions have been executed?

I have functions than run MySQL queries and do other stuff:
insert_object($object_info);
insert_time($time);
...

Some functions use other functions to do their job.
Each of these functions can generate a message if something went wrong: "time already entered", etc...

I don't want to do echo calls inside the functions: I want them to return the messages if there have been some.

But what's the best way to do that? concat the messages of all functions in a really big string? Use an array, but I have the risk of getting multiple dimensions arrays.

How is this done usually in applications?

[OhLordy]

Either write them to a file or to a database.
Have some function which is called whenever an error happens. Two arguments, error_type, and error_description.
Hoope this helps
Rob

[TheJuice]

Oh yes that's a good idea to log the errors this way.

I thought of another way though: make a global variable $errors that is an array.
Each time there is a problem, I add an element to the global array, and the array is available everywhere.

I know it is not advised to use global variables, but I think it is quite useful here...