Hi, I want to change member of structure under double pointer. Do you know how?
Example code
typedef struct {
int member;
} Ttype;
void changeMember(Ttype **foo) {
//I don`t know how to do it
//maybe
*foo->member = 1;
}
Thanks for any help.
...
Simple question here: is there any way to convert from a jagged array to a double pointer?
e.g. Convert a double[][] to double**
This can't be done just by casting unfortunately (as it can in plain old C), unfortunately. Using a fixed statement doesn't seem to resolve the problem either. Is there any (preferably as efficient as possib...
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...
In short, I would like to do this:
const char **stringPtr = &getString();
However, I understand that you can't & on rvalues. So I'm stuck with this:
const char *string = getString();
const char **stringPtr = &string;
I can live with two lines. Am I introducing problems with this hack? I should have no fear of passing stringPtr out ...
Hi,
I have seen this in some book/ tutorial.
When you pass in the head pointer (of linked list) into a function, you need to pass it as a double pointer.
For eg:
// This is to reverse a linked list where head points to first node.
void nReverse(digit **head)
{
digit *prev=NULL;
digit *curr=*head;
digit *next;
while(cu...
Suppose I have an array of pointers to char in C:
char *data[5] = { "boda", "cydo", "washington", "dc", "obama" };
And I wish to sort this array using qsort:
qsort(data, 5, sizeof(char *), compare_function);
I am unable to come up with the compare function. For some reason this doesn't work:
int compare_function(const void *name1,...