Re: Basic c question again - type casting

Lim Hock-Chai wrote:

...
I did below and it compile. Not sure if it will run correctly or not.
But at least it compiled :) ...
UAM * data;
logECD_STP((char **) &data);

As a general rule, you should aim to code without any casts. Sometimes they are necessary, but you should do everything you can to avoid them.

As a hard-and-fast rule: Never code a cast unless you understand _completely_ what the effect will be. You have to understand exactly what the cast means in terms of the layout of storage it is describing, and you have to understand exactly what is the actual storage that you are casting. Only then can you assess whether the cast is valid.

Casting is basically a way to lie to the compiler, and that is A Bad Thing to do. (I see that Marty already made this point, but I'm re-making it anyways)

You are telling the compiler that your variable "data" is a "pointer to character", but it is really a "pointer to UAM". Since you are only passing 1 parameter to logECD_STP(), it is likely that the function is treating the parameter as null-terminated string. It is equally _unlikely_ that your variable "data" actually is a null-terminated string.