struct

A queue in C using structs and dynamic memory allocation (linked list)

I am tasked with making a queue data structure in C, as a linked list. Our lecturer gave us a large amount of code to implement a stack, but we have to adapt it to create a queue. The code our lecturer gave us ends up not compiling and segfaulting at the exact same point as the code I wrote for the queue. I'm very new to structs, malloc ...

Dynamic memory inside a struct

Hello, I'm editing a piece of code, that is part of a big project, that uses "const's" to initialize a bunch of arrays. Because I want to parametrize these const's I have to adapt the code to use "malloc" in order to allocate the memory. Unfortunately there is a problem with structs: I'm not able to allocate dynamic memory in the struct...

How does NSValue do its magic?

I have an MVC application. The model has a property that is a struct NSSize. It is writable like this: - (void)setSize:(NSSize)aSize; The view sets this NSSize using key-value-coding. However, you can not key-value-code a struct, so I wrapped it in an NSValue-object like this: [theView setValue:[NSValue valueWithSize:mySize] ...

passing different structs to a function in c

I have different structures that need to be filled out the same way. The only difference is that they are filled based on different data. I was wondering if it's possible to pass different structures to a certain function. What I have in mind is something like: struct stu1 { char *a; int b; }; struct stu2 { char *a; i...

Wondering about a way to conserve memory in C# using List<> with structs

I'm not even sure how I should phrase this question. I'm passing some CustomStruct objects as parameters to a class method, and storing them in a List. What I'm wondering is if it's possible and more efficient to add multiple references to a particular instance of a CustomStruct if a equivalent instance it found. This is a dummy/exampl...

Making Global Struct in C++ Program

Hello world! I am trying to make global structure, which will be seen from any part of the source code. I need it for my big Qt project, where some global variables needed. Here it is: 3 files (global.h, dialog.h & main.cpp). For compilation I use Visual Studio (Visual C++). global.h #ifndef GLOBAL_H_ #define GLOBAL_H_ typedef struc...

c struct pointer issues

I'm trying to cast a struct into another struct but I'm having incompatible pointer issues within the cast and the malloc under some_func (structs layout are the same) struct stu1 **some_func(struct stu1 *my_struct) { my_struct = (struct stu1 **)malloc(sizeof(struct stu1 *)*total_size); for(i=0;i<20;i++){ my_struct[i] = (st...

Declaring a prototype of type "struct" - C

I've been racking my brains on this for a while, I'm simply trying to create a method that returns a struct as I wish to return two int's. My prototype for the method is as follows: typedef struct RollDice(); Also the method itself: typedef struct RollDice() { diceData diceRoll; diceRoll.dice1 = 0; diceRoll.dice2 = 0; return d...

Convert array of hashes to array of structs?

Let's say I have two objects: User and Race. class User attr_accessor :first_name attr_accessor :last_name end class Race attr_accessor :course attr_accessor :start_time attr_accessor :end_time end Now let's say I create an array of hashes like this: user_races = races.map{ |race| {:user => race.user, :race => race} } ...

C Struct as an argument

I'm wondering what's the difference between sample1 and sample2. Why sometimes I have to pass the struct as an argument and sometimes I can do it without passing it in the function? and how would it be if samplex function needs several structs to work with? would you pass several structs as an argument? struct x { int a; int b...

Deserializing a struct with SoapFormatter

I added a new member to an existing class that's serialized. The SoapFormatter was used on released versions, so this can't be changed. The main problem is deserializing old versions that don't have this new member. The new problem is when ISerializable is added to the class, structs in that class can no longer be deserialized. I get...

InvalidCastException in DataGridView

(Using VS 2010 Beta 2 - .Net 4.0 B2 Rel) I have a class, MyTable, derived from BindingList where S is a struct. S is made up of several other structs, for example: public class MyTable<S>:BindingList<S> where S: struct { ... } public struct MyStruct { public MyReal r1; public MyReal r2; public MyReal R1 {get{...} set...

Are arrays stored as a pointer or in their entirety inside C struct's? (was: How to dump structs to disk when some fields are pointers?)

Hello, I'm writing a FUSE plugin in C. I'm keeping track of data structures in the filesystem through structs like: typedef struct { block_number_t inode; filename_t filename; //char[SOME_SIZE] some_other_field_t other_field; } fs_directory_table_item_t; Obviously, I have to read (write) these structs from (to) disk at som...

Getting name and type of a struct field from its object

For example, I have a struct which is something like this: struct Test { int i; float f; char ch[10]; }; And I have an object of this struct such as: Test obj; Now, I want to programmatically get the field names and type of obj. Is it possible? This is C++ BTW. ...

How can I access structure fields by name at run time?

The C faqs explain it in a way, here is the link. But I can't understand it, Somebody can explain it for me? Or give me another way? Thanks so much! ...

C Struct initialization : strange way

While reading a code I came across, the following definition and initialization of a struct: // header file struct foo{ char* name; int value; }; //Implementation file struct foo fooElmnt __foo; // some code using fooElmnt struct foo fooElmnt __foo = { .name = "NAME"; .value = some_value; } What does this mean in C and how is...

How can I align an element of a struct?

Is there any way to force an alignment of a particular element of a struct using a GNUism? ...

Initializing a Global Struct in C

What is the best way to accomplish the following in C? #include <stdio.h> struct A { int x; }; struct A createA(int x) { struct A a; a.x = x; return a; } struct A a = createA(42); int main(int argc, char** argv) { printf("%d\n", a.x); return 0; } When I try to compile the above code, the compiler reports th...

Naming conventions for private members of .NET types

Normally when I have a private field inside a class or a struct, I use camelCasing, so it would be obvious that it's indeed private when you see the name of it, but in some of my colleagues' C# code, I see that they use m_ mostly or sometimes _, like there is some sort of convention. Aren't .NET naming conventions prevent you from using...

Class declaration confusion - name between closing brace and semi-colon

class CRectangle { int x, y; public: void set_values (int,int); int area (void); } rect; In this example, what does 'rect' after the closing brace and between the semi-colon mean in this class definition? I'm having trouble finding a clear explanation. Also: Whatever it is, can you do it for structs too? ...