I've been working for some number of days on this code to take information about movies from both a file and the user, store the infos in an array of structs, and at the end, write all the info out to a file. I'm having some problems with an error message reading:
"prog.c:102:11: error: subscripted value is neither array nor pointer nor vector"
this error occurs in many lines (which I will label specifically below -- they are everywhere where I am trying to access/modify an individual element of a struct element of the array).
A few examples of where I am having the problems are lines:
39, 52-55, 70, 72, and 86 (and more of the same exact variety).
I am obviously rather systematically doing something wrong, but I am quite certain all of these are the exact same mistakes.
I pull up also 2 or 3 other errors, but I don't think they are related and should be able to fix them quickly once I work out this conundrum.
#include <string.h>
#include<stdlib.h>
#include <stdio.h>
int moviecount =0;
typedef struct{
int year;
I want to access the elements of my array dynamically. So far I've only figured out how to do this manually. if I tried it like this my code would work but there should be a better way right?
I am trying to retrieve the elements in an array to print them. I am pretty sure I have everything right, but it is not working. There are 5 values in the array {3, 4, 10, 5, 6}, but the first two elements (supposed to be 3,4) are coming out a 0,-2654238590. The last three elements are coming out correct.
void addDynArr(DynArr *v, TYPE val) { /* FIXME: You will write this function */ assert(v != 0); //resize if necessary if(v->size >= v->capacity)
Now I have to write a function show_exam_descending(Data d, string subCode) when I call show_exam_descending(d, "ENGL_S12") the program will execute to show all the students' exam scores in ENGL_S12 in DESCENDING order...
For this to run, I have declared a struct Data:
struct Data { string subjectCode; int studentCode; double examScore; );
For the search, I have written a function before to load all the data from the document by using pointer and dynamic arrays. It works so well. What troubles me is the way to swap the elements (i.e. examScore) of different students in struct dynamic arrays. I am able to display all of them, but don't know how to swap.
I'm confused about accessing elements from arrays. Supposed I have an array of pointers to char:
char *names = { "John", "Rose", "Steven" };
To access one of the strings, should I use names[ 0 ][ i ], where i is an index in the set ( 0, 1, 2 ), or should I use names[ i ]? I would think it would be the first option, because this array has 1 dimension that contains others arrays, right?
error: request for member 'character' in '* ptr', which is of non-class type 'datastructure*' error: request for member 'character' in '* ptr', which is of non-class type 'datastructure*'
These errors are related to " *ptr->character='a'; printf("Ptr: %c",*ptr->character); "
I want to access "character" data inside the structure "trial" by a pointer to pointer "ptr" inside function "function",but I couldn't find a way to do this.
The program I'm working on is a very basic relational database. I've isolated my problem for simplicity. I get a segfault right here when I try to access db->relationCount. I tried printing db->relationCount from within loadDB and that worked,
I've been reading the tutorials on Friendship and Inheritance [URL] ..... but I still don't understand why I can't access members of the same struct type.
The code above is located in a source file, where the function isAlphanumeric passes a char value, and Message is the struct containing the string I want to access. Below is the declaration of the struct and string located in the corresponding header file.
My frustration comes when I try to call and assign messageText like the tutorial does to its private members, but I keep getting an error saying I can't access the string because it is a private member. Is there a way to access the string without having to pass it through the function wordBeginsAt?
I have a vector (structures) in a struct (instances). I make a declaration of this struct called instance. The vector is a 3-layer vector of pointers, like so:
vector < vector < vector<scene::IAnimatedMeshSceneNode*> > > structures; (The type is from Irrlicht 3D). I have 3 nested "for" loops which looks similar to the following:
for (int a = 0; a < instance.structures.size(); a++) { /*note:vector size previously set*/ for (int b = 0; b < instance.structures[a].size(); b++){ for (int c = 0; c < instance.structures[a][b].size(); c++) {
if (1) { //checking value of variable not included in snippet
These are currently referencing the pointers, it seems. The program compiles but crashes at this point. I need them to reference the values of the pointers. Problem is, I don't know where to put the dereference operator (*). Where should it go?
I currently have a file which allows inputs to record different transistor types. I then have the task of accessing this structure, find a certain manufacturer ID, and print the information about this particular transistor.
My problem is accessing the array to search through.
Here is my code:
Code: #include "stdio.h" const int IDLEN=30; //All constant values defined const int POLARITYLEN=3; const int MAXSTOCKITEMS=10; //First structure defined struct TransistorRec {
[Code]......
The errors I am currently getting are on line 54 'expected primary-expression before "struct"' and on line 60 ' 'maunfacturersID' undeclared'
I'm currently working on the ioquake3 engine . The ioquake3 engine is separated into 2 different main threads at runtime: the gamecode and the engine. Both are communicating but not all information and my problem resides here.
In the gamecode, there's a struct called gentity_t which contains a lot of fields:
Code: typedef struct gentity_s gentity_t; struct gentity_s { entityState_ts;// communicated by server to clients entityShared_tr;// shared by both the server system and game // DO NOT MODIFY ANYTHING ABOVE THIS, THE SERVER // EXPECTS THE FIELDS IN THAT ORDER! //================================ struct gclient_s*client;// NULL if not a client
[Code] ....
This whole entity is passed to the engine at runtime, but only the first two fields are declared for the engine:
Code: // the server looks at a sharedEntity, which is the start of the game's gentity_t structure typedef struct { entityState_ts;// communicated by server to clients entityShared_tr;// shared by both the server system and game } sharedEntity_t;
My problem is that I need to access the health field of gentity_t from the engine. Technically, this is possible, but the health field is not declared in sharedEntity (which is the same memory address than gentity_t in the gamecode), so this is not straightforward.
I am looking for an elegant way to do this, and my constraint is that I must not edit the gamecode, only the engine.
The solutions I've thought:
- Just copy the whole gentity_t fields into sharedEntity_t. This would work I think but would be redundant, and I would like to avoid copying this huge set of fields.
- Include the two headers files declaring the gentity_t and sharedEntity_t structs, and create a Getter and a Setter functions that would cast a gentity_t over a sharedEntity_t and return/set a field. The problem is that I can't simply include them because they are both including some common headers files and this produce a recursive include error (and I can't modify the files to add a check, these are normally in the gamecode).
- Directly access the health field using a clever memory pointer, but I don't even know if that's possible given the huge number of fields prior health with many different types?
I am parsing a binary data file by casting a buffer to a struct. It seems to work really well apart from this one double which is always being accessed two bytes off, despite being in the correct place.
If I attempt to print GROSS using printf("%f", row->GROSS) I get 0.0000. However, if I change the type of GROSS to char[8] and then use the following code, I am presented with the correct number...
Code:
typedef struct example { double d; }
example; example *blah = (example*)row->GROSS; printf("%f", blah->d);
Write a program that reads in the names and the ages of ten people. Store these data in two arrays (make sure that the entered names are not longer than the array size you choose). Then produce a table of ten lines, with each line giving the name and age of a person along with the (positive or negative) deviation of that person's age from the average age. The code I wrote to fill in the arrays looks as follows
Code: #include<stdlib.h> #include<stdio.h> int main() { // begin main() // array length
[Code]....
When I compile it, it gives me warnings that few of the variables I declared aren't used, but that is not affecting the program at all. When I run the program, it allows me to pass the names and ages into the arrays, but when it comes to displaying them, I'm getting a 'Segmentation fault'. I used very similar code in Java to write the program, and it worked fine so what is the problem with C then?
I'm okay with 2-dimensional arrays, but when I get to 3 or more, I can't seem to wrap my head around how to assign and/or pull values from specific parts.
To give an example, let's take the following example:
We know that a player can take up to 5 total quests, and each quest can have a max of 5 tasks.
Let's assume I have the following multi-dimensional array holding all of a players quest data:
quests[0] = 78;// Store the questID quests[0][0] = 3945;// Store the 1st creature ID quests[0][1] = 2230;// Store the 2nd creature ID quests[0][2] = 3045;// Store the 3rd creature ID quests[0][0][0] = 2;// Store how many needed of the 1st creature quests[0][1][0] = 5;// Store how many needed of the 2nd creature quests[0][2][0] = 13;// Store how many needed of the 3rd creature
As we know, the above code can't be done. How do I assign certain values to each specific dimension?
I have a contiguous sequence of section headers in a file (all the data in the file is stored in void * data), where each section header is the same size and has the same fields in the same order. So it's laid out like an array.
I have to:
- Use an offset value and the number of section headers variables to identify the location and length of the section header table (these are hdr.offset and hdr.length respectively). - The offset value shows the distance between the start of the file and the start of the first section header (so I need a pointer to the start of the first section header) - Apply a typecast to location of the section header table to process it as an array of section headers.
Here is what I have done, but I am getting a segmentation fault. What am I doing wrong? How do I fix this?
typedef struct { unsigned int name; unsigned int type; } SectionHeader;
Write a program using user-defined function which accepts an integer array and its size as arguments and assign the elements into a two dimensional array of integers in the following format: If the array is 1,2,3,4,5,6, the resultant 2D array is
I am having problem in writing the code for the problem "To assign the elements of 1-D integer array into 2-D array of integers such as if the array is 1,2,3,4,5,6 The resultant 2-D array should be like :
I wrote this simplified version of a program i am writing that parses data in UDP packets. In the process of doing so i pretty much answered all my questions and fix all the problems i was having.
decodeSystemMap function will be in loop, and will proccess packets that have mostly the same data, only a few items will be added or changed or deleted.
whats the best way to check if there are any new, deleted, or removed items in the packet and only modify those? Is there anything unsafe / dangrous about the way the code is now?
Code: /* * File: main.c * Author: david * * Created on May 23, 2013, 11:57 AM */
