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memory_get_peak_usage() with “real usage”
...ent is set to true the PHP DOCS say it will get the real size of memory allocated from system. If it's false it will get the memory reported by emalloc()
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Why do we not have a virtual constructor in C++?
...he second line postulates the notation new p->Base() to request dynamic allocation and default construction of another Derived object.
Notes:
the compiler must orchestrate memory allocation before calling the constructor - constructors normally support automatic (informally "stack") allocation...
How to initialise memory with new operator in C++?
...ing to get into C++ and I want to pick up some good habits. If I have just allocated an array of type int with the new operator, how can I initialise them all to 0 without looping through them all myself? Should I just use memset ? Is there a “C++” way to do it?
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Under what circumstances are linked lists useful?
...any linked lists are stored in an array.
It avoids doing many small (de)allocations on inserts/deletes.
Initial loading of the hash table is pretty fast, because the array is filled sequentially (plays very nice with CPU cache).
Not to mention that a chaining hash table is expensive in terms of ...
How do I trim leading/trailing whitespace in a standard way?
... pointer to a substring of the original string.
// If the given string was allocated dynamically, the caller must not overwrite
// that pointer with the returned value, since the original pointer must be
// deallocated using the same allocator with which it was allocated. The return
// value must N...
Android emulator failed to allocate memory 8
...e it starts working. Source: stackoverflow.com/questions/7222906/failed-to-allocate-memory-8
– Juha Palomäki
Oct 7 '13 at 12:55
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show 1 mo...
strdup() - what does it do in C?
...e as the following code:
char *strdup(const char *src) {
char *dst = malloc(strlen (src) + 1); // Space for length plus nul
if (dst == NULL) return NULL; // No memory
strcpy(dst, src); // Copy the characters
return dst; // Re...
When should I use malloc in C and when don't I?
I understand how malloc() works. My question is, I'll see things like this:
6 Answers
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Declaring variables inside loops, good practice or bad practice?
...n be performed more efficiently by the compiler (most importantly register allocation), since it knows that the variable cannot be used outside of the loop. For example, no need to store the result for later re-use.
In short, you are right to do it.
Note however that the variable is not supposed ...
Why should I use a pointer rather than the object itself?
...
It's very unfortunate that you see dynamic allocation so often. That just shows how many bad C++ programmers there are.
In a sense, you have two questions bundled up into one. The first is when should we use dynamic allocation (using new)? The second is when should w...