malloc and free usage

[Dedalus]

Hi all,

I know that each time we allocate memory onto the heap (malloc, calloc, realloc..) once we finish we have to free it in order to avoid memory leaks.

Just to improve my skills I'm reading the C code of paste.c (the linux command). Now without go through code details, why in the code I see a couple of xmalloc and there are no free() call?
Shouldn't we free the memory we allocated?

Thanks in advance

[grumpy]

Generally, yes, it is advisable to ensure your programs explicitly release all memory they allocate. Not everyone does it though. With some it is a calculated (hopefully low) risk. With others, it is laziness or incompetence.

"Advisable" is not the same as "mandatory".

The unix past command is pretty simple. Given that, the developers may have decided decided to be lazy about memory deallocation, and rely on the operating system cleaning up when the program exits.

Another possibility is that the program calls realloc(). If the size supplied to realloc() is zero, it has the same net effect as free().

[Dedalus]

Hi,

thanks for your help I appreciate it

[CodeMonkey]

It is also important to keep in mind how long your program will be running. For scientific applications, or server-side stuff, a program may regularly (constantly) allocate resources and run for weeks. Then what happens? In my humble opinion, all memory should be explicitly deallocated when it is no longer needed.