Menu
My question is about C free() function for deallocating memory blocks previously allocated with malloc().
If i have a struct data type compose of several pointers, each of them pointing to different memory locations, what would happen to those memory locations if i apply free() on the struct? will that locations be free too? or just the memory block that allocate the pointer?
710
You have to free the struct if you allocated it dynamically. You have to free its members before deallocating the struct if you allocated the members dynamically and don't have a reference to them anywhere else. From your example, yes, you need to free() l.
free() is a function which takes in a pointer. &x is a pointer. This code may compile, even though it simply won't work. If we pretend that all memory is allocated in the same way, x is "allocated" at the definition, "freed" at the second line, and then "freed" again after the end of the scope.
Concrete answer: This assigns a pointer to a constant string to your char* a , by doing so you loose the pointer to the memory allocated in the first line, you should never free constant strings.
free() just declares, to the language implementation or operating system, that the memory is no longer required.
No. They won't be freed. You have to free them "manually". The malloc knows nothing about the content of your struct (it does not know it is a struct at all, it is just a "piece of memory" from its point of view).
62
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
