I got the following problem: I have an array of char pointers char *opts[] = { "-a", "--append", "-b" }; and a command name stored in char cmd[] = "ls"; Now I need to compute all possible combinations, which I've done using the GNU Scientific Library and execute the command with the compute combinations. The problem I have is ho...
Ok guys, i'm very beginner and trying to enter string to a char array using pointers..and then display what i've written. There're two things i want to ask about. First , if i didn't want to specify a size for the array and just want it to expand to contain all string i've entered ..how is that ? And second after i enter the string and...
I am working on understanding recursion, and I think I have it down alright... I'm trying to build a search function (like the std::string.find()) that searches a given string for another string for example: Given (big) string: "ru the running cat" search (small) string: "run" I'm trying to return a index for the where the wor...
hi , int * (*) (int * , int * (*)()) I'd like to know what type is it ? , can someone give an example of a declaration using this type. any help would be great. thanks. ...
Firstly, sample codes: Case 1: typedef char* CHARS; typedef CHARS const CPTR; // constant pointer to chars Textually replacing CHARS becomes: typedef char* const CPTR; // still a constant pointer to chars Case 2: typedef char* CHARS; typedef const CHARS CPTR; // constant pointer to chars Textually replacing CHARS becom...
Hi all , This is my second problem today, pointers are giving me nightmares . I'm trying to make a program that do the same thing that strcpy() function do.. Once i try it..it crashes and i'm 100% sure that's a pointers issue in my code. I think because there is some sort of an unintiallized pointer(*copied) ..But i've assigned NULL to i...
In VB6 I'm making a call to the Windows API DnsQuery. Private Declare Function DnsQuery Lib "dnsapi" Alias "DnsQuery_A" ( _ ByVal lpstrName As String, _ ByVal wType As Integer, _ ByVal Options As Long, _ ByVal pServers As Long, _ ppQueryResultsSet As Long, _ ByVal pReserved As Long) As Long Private Type VBDnsRecord ...
I am having trouble understanding how to assign memory to a double pointer. I want to read an array of strings and store it. char **ptr; fp=fopen("file.txt","r"); ptr=(char**)malloc(sizeof(char*)*50); for(int i=0;i<20;i++) { ptr[i]=(char*)malloc(sizeof(char)*50); fgets(ptr[i],50,fp); } instead of thi...
Hi I have a text file containing two arrays and one value(all integers) like this 3 90 22 5 60 33 24 Where the first number stands for how many integers to read in. I can read in all this in one function. Do I need several functions to be able to use the different matrices and the first variable? ifstream in(SOMEFILE.dat); if...
Objective c | xcode | iphone question Im building a model(data) class for a monetary transaction and have kind of a basic/noob question regarding pointers and object copying. The Transaction class I'm creating contains 4 or 5 ivars/properties that represent object type variables. now when I get the user entered data from the view contro...
Hi! It might be that the problem is straight forward but I don't get my head around it. I have the following iPhone code for(int x = 0 ; x < [allFriends count] ; x++) { Friend *f = [[Friend alloc] init]; f = [allFriends objectAtIndex:x]; if([uid isEqualToString:[f uid]]) { ...
Help me in solving 2 questions on pointers: 1)Please tell me why do I get 'segmentation fault' when I run following snippet main() { char *str1 = "united"; char *str2 ="front"; char *str3; str3 = strcat(str1,str2); printf("\n%s",str3); } 2)Why don't I get output in following code: main() { ...
I'm trying to debug a program I've written. According to the debugger a particular void * holds the value 0x804b008. I'd like to be able to dereference this value (cast it to an int * and get it's value). I'm getting a Segmentation Error with this code. (The program with the void * is still running in the background btw - it's 'paused')...
Possible Duplicate: What are the barriers to understanding pointers and what can be done to overcome them? Was just wondering if anyone could "point me" to a good tutorial on pointers Would be very greatful Thanks ...
Can someone check my understanding and correct me if i am wrong? int p = 5; //create an int holding 5 int *ptr; //create a pointer that can point to an int *ptr = &p; // not sure - does this mean that my pointer now points to memory address five, or that the memory address my pointer points at contains 5? Sorry for the basic questio...
I am posting a code. using System; using System.Runtime.InteropServices; class TestPointer { public static void Main(string[] args) { if (args.Length == 0) { unsafe { int t = 8; int* p = &t; IntPtr addr = (IntPtr)p; ...
GCC gives me an "array type has incomplete element type"-error message when i try to compile this: typedef struct _node node; struct _node{ int foo; node (*children)[2]; int bar; }; In memory the struct should look like this 0x345345000000 foo 0x345345000004 pointer to 1. child node 0x345345000008 pointer to 2. child node 0x345345...
I have an (for C++ programmers better than me) simple problem with classes and pointers. I thought about posting example code describing my problem but I found it easier to just explain it in words. Assuming I have three classes: Class A: The main class - it contains an instance of both B and C. Class B: This class contains a method t...
Hi, i was hoping for some help, opposed to full solutions and i have an idea that i need to know what i am doing wrong when trying to implement basically i am trying to remove spaces from the end of an array of characters in c this is what i am doing i have a method to work out the length of the string and store it in to an int i se...
I am trying to remove spaces from the end of a char array (string). This is the pseudo code of what I am doing, but it keeps deleting the whole string: if(string length - 1 != a space) return Otherwise, it must equal a space, so while *mypointer-- != a space //This should loop back to where there is a character. Outside of the...