Examples of using Malloc function in English and their translations into Russian
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Colloquial
This is the 6th part,which focuses on the malloc function.
Assume the malloc() function is used 1000 times in the code.
In C++, this allocation is usually performed by the malloc function or new operator.
If the malloc function is unable to allocate the memory buffer, it returns NULL.
However, the found defects will be enough for us to discuss the malloc function.
The comment tells us that the'malloc' function was used earlier to allocate memory.
He argues that they understand what they are doing when they don't check the result of the malloc function call.
Just because the malloc() function possesses an argument of memsize type and 5 is quite an appropriate value.
To learn more about it see the blog-post on our site" Magic constants and malloc() function.
After the third call, malloc function will return the array's address outside the range of the first two Gbyte.
By the way, there is another excuse for developers,why they don't check what the malloc function returned.
A pointer returned by the'malloc' function or any other similar function is summed up with some number.
As the header file"stdlib. h" is disabled,the C compiler considers that malloc function will return int type.
If the malloc function failed to allocate memory, it is unlikely that my program will continue to function properly.
If the header file"stdlib. h" is not included,the C compiler supposes that the malloc function will return the int type.
I hope now you have a new look at the malloc function, check pointers and warnings of the PVS-Studio code analyzer.
The only way to write reliable and correct code is to always check the result that is returned by the malloc function.
According to the definition of the malloc() function, the argument which determines the size of the allocated memory is of the size_t type.
There are 4 reasons at once, each of them is enough to prove that it is so necessary to write a check after you call the malloc function.
Now the analyzer thinks that the malloc function cannot return NULL and, therefore, will not issue the V522 warning for the following code.
Let's see what happens to data when we allocate them in dynamic memory using the malloc function or the new operator.
Any normal program should check the pointers which the malloc function returns and properly handle the situation when the memory allocation failed.
The analyzer detected a potential error relating to using a dangerous expression serving as an actual argument for malloc function.
Presence of a constant in an expression which is a parameter for malloc() function does not necessarily means that V118 warning will be always shown on it.
I'm not making this up, I have talked with people who consider this approach to be appropriate andconsciously never check the result that the malloc function returns.
Looking at a fresh code fragment, it's not easy to assume that the malloc function works incorrectly, because the header file stdlib.h is not included.
The memory for the number string was allocated using malloc() function, herewith before checking the pointer it is dereferenced several times and passed into the function memcpy() as an argument, which is invalid.
The function'malloc()' is used to allocate memory while the'delete[]'operator is used to release it.
For instance, you can write your own function malloc() that will return NULL from time to time even when there is some memory left.
Looking through the definition of function malloc we will see that its formal argument assigning the size of the allocated memory is represented by type size_t.