What does PTR mean in code?
The point of this hint is to tell the size of the operand. You’re writing to a point in memory. As you’re only giving a 0, it doesn’t know if it should write a byte, or word, or doubleword. The dword ptr means “write a doubleword”. Yes, it stands for pointer, because you put a memory address as destination.
What is mov byte ptr?
mov byte ptr [value_two],”e” : “Byte ptr” lets the assembler know you want to store a byte. This must be done, because value_two was declared as a word. (DW) If we would have declared it a byte (DB), like value_one, you could have ommited the “byte ptr”.
What is PTR operator?
The PTR operator specifies a type for a memory address. The type may be one of the following: Type. Description. BIT.
What does dword ptr mean?
the size of
Basically, it means “the size of the target operand is 32 bits”, so this will bitwise-AND the 32-bit value at the address computed by taking the contents of the ebp register and subtracting four with 0.
What does * ptr mean in C?
It has two meanings: // When * is used when declaring a pointer char *ptr means “pointer to” a character, e.g., char *ptr = “andrew”; char c; // but when not used in the declaration of a pointer (e.g., *ptr). The indirection operator * // is used to access the data by means of pointer ptr.
What is ptr in linked list?
Basic element of a linked list is a “record” structure of at least two fields (a class definition with these instance variables). next ptr is a reference to the next element in the structure. There can be multiple reference fields but we won’t consider that now. pointer/reference/link are synonymous in this discussion.
What does x86 call do?
The CALL instruction performs two operations: It pushes the return address (address immediately after the CALL instruction) on the stack. It changes EIP to the call destination. This effectively transfers control to the call target and begins execution there.
What does ptr mean in C++?
Example explained. Create a pointer variable with the name ptr , that points to a string variable, by using the asterisk sign * ( string* ptr ). Note that the type of the pointer has to match the type of the variable you’re working with.
What is the difference between int * ptr and int * ptr?
To the compiler, there is no difference between the two declarations. To the human reader, the former may imply that the “int*” type applies to all declarations in the same statement. However, the * binds only to the following identifier. For example, both of the following statements declare only one pointer.
What is PTR in algorithm?
We begin by describing the penalized trust region (PTR) algorithm. This is a particular SCP method that has been widely used for fast and even real-time solution of nonconvex problems like Problem 41, where the value of is fixed [27,29, 52] .
What does PTR mean in Java?
When you use ptr in a program, you are referring to the actual pointer, that is, the memory address that is contained in the variable ptr. To refer to the value that is stored at that address, you would use the notation *ptr.
What does a byte PTR mean in memory?
You need to make it explicit with a size specification: byte ptr indicates that the memory operand refers to a byte in memory as opposed to a word or dword.
What is the meaning of ebp-9 byte PTR?
EBP-9 is simple math, take the value of the EBP register and subtract nine from it. The square brackets mean to then take that result and treat it like an address to a location in memory. The byte ptr tells you how large of a value to grab from that memory location, in this case a single byte.
What does square brackets mean in CMP byte PTR?
The square brackets mean to then take that result and treat it like an address to a location in memory. The byte ptr tells you how large of a value to grab from that memory location, in this case a single byte. If it were a word ptr, then you would dereference two bytes (in little-endian byte-order, since this is Intel architecture I think).
How is the PTR operator used in Assembly?
Syntax: type PTR name Description: The PTR operator is used to define a memory reference with a certain type. The assembler determines the correct instruction to assemble based on the type of the operands to the instruction. There are certain instances where you may specify an operand that has no type.