Solved

small question about pointer array

Posted on 2006-11-19
3
260 Views
Last Modified: 2010-04-01
     char* pszMonths[] ={"invalid",
                          "January",
                          "February",
                          "March",
                          "April",
                          "May",
                          "June",
                          "July",
                          "August",
                          "September",
                          "October",
                          "November",
                          "December",};


In this statement there are 12 pointers that points at 12 months. Every pointer has 4 bytes in memory. The thing i don't understand is:

Where are these strings stored in memory?

pszMonths[1] is the pointer that points at January. Let's say 0x111 is the address of "January" But how command do tell "store 'January' at 0x111 " ? Is it stored simultaneously with the pointer array? (sorry for my english)
0
Comment
Question by:data_grrr
  • 2
3 Comments
 
LVL 7

Accepted Solution

by:
UrosVidojevic earned 125 total points
ID: 17975828
The array you declared is an array of pointers to chars. Pointer to some object is actually its address (address of its first byte).

So basicly this is array of addresses of begginings of your strings, so elements of your array may look like this in memory:

pszMonths[0]   ---> 0x0400 and this is address of the first character of your first string.
pszMonths[1]   ---> 0x0700 and this is address of the first character of your second string.
...
pszMonths[12] ---> 0x1004 and this is address of the first character of your 12th string.

And memory looks like this:

0x0400 -> i
0x0401 -> n
0x0402 -> v
...
0x0700 -> J
...

The choice of addresses where compiler puts your strings is compiler's job so you don't need to worry about that.  Of course compiler tends to put your strings one after another without empty spaces between them in memory.

So it is very probbably that memory will look like this

i n v a l i d \0  J a n u a r y \0 F e b r u a r y...

Regards, U.V.
0
 
LVL 7

Expert Comment

by:UrosVidojevic
ID: 17975835
\0 is an character with ASCII code 0 that marks the end of some char array.
If you need more help, just say...
0
 
LVL 1

Author Comment

by:data_grrr
ID: 17975842
thanks, now i understand :)
0

Featured Post

Free Tool: SSL Checker

Scans your site and returns information about your SSL implementation and certificate. Helpful for debugging and validating your SSL configuration.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

What is C++ STL?: STL stands for Standard Template Library and is a part of standard C++ libraries. It contains many useful data structures (containers) and algorithms, which can spare you a lot of the time. Today we will look at the STL Vector. …
Basic understanding on "OO- Object Orientation" is needed for designing a logical solution to solve a problem. Basic OOAD is a prerequisite for a coder to ensure that they follow the basic design of OO. This would help developers to understand the b…
The goal of the tutorial is to teach the user how to use functions in C++. The video will cover how to define functions, how to call functions and how to create functions prototypes. Microsoft Visual C++ 2010 Express will be used as a text editor an…
The viewer will learn how to user default arguments when defining functions. This method of defining functions will be contrasted with the non-default-argument of defining functions.

685 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question