How can I trap an API call by windows

[Ali Akbar]

Hi everyone,
I just wanted to know how my program can trap a particular API
call by windows. (The idea is that I want to hook all the open text
boxes and keep hooking new ones as and when they are created).

So for this i want to trap the CreateWindow or CreateWindowEx API
as that I can keep track of the handles etc. I have an idea that
this can be done by mapping the entry points of kernel32.dll,
gdi32.dll etc, just like how SoftIce does, but Im not very sure about
this.

Any suggestions or help would be greatly appreciated.

Thanks in advance,
Ali.

[Kevin Goodsell]

Ali Akbar wrote:

Hi everyone,
I just wanted to know how my program can trap a particular API
call by windows.

Then you probably wanted a Windows programming group. This group is for
discussion of the C language as defined by the international C standard,
which has nothing to say about Windows or trapping APIs (whatever that
means).

-Kevin
--
My email address is valid, but changes periodically.
To contact me please use the address from a recent posting.

[lallous]

"Ali Akbar" <al******@yahoo.com> wrote in message
news:bd**************************@posting.google.c om...

Hi everyone,
I just wanted to know how my program can trap a particular API
call by windows. (The idea is that I want to hook all the open text
boxes and keep hooking new ones as and when they are created).

So for this i want to trap the CreateWindow or CreateWindowEx API
as that I can keep track of the handles etc. I have an idea that
this can be done by mapping the entry points of kernel32.dll,
gdi32.dll etc, just like how SoftIce does, but Im not very sure about
this.

Any suggestions or help would be greatly appreciated.

Thanks in advance,
Ali.

Hello,

Although this is not a "C" question, you can still search for "Detours" by
Microsoft or "API Hooking" on google.

--
Elias

[glen herrmannsfeldt]

Ali Akbar wrote:

Hi everyone,
I just wanted to know how my program can trap a particular API
call by windows. (The idea is that I want to hook all the open text
boxes and keep hooking new ones as and when they are created). So for this i want to trap the CreateWindow or CreateWindowEx API
as that I can keep track of the handles etc. I have an idea that
this can be done by mapping the entry points of kernel32.dll,
gdi32.dll etc, just like how SoftIce does, but Im not very sure about
this.

The only way that I can think of that is on topic here is to do
something like:

#define CreateWindow myCreateWindow

in the program you want to trap, and then separately write a
myCreateWindow function that does whatever you want to do
before or after calling the real CreateWindow function.

That may or may not satisfy your question.

Another way, though getting off of standard C, is to go through
the system library with a binary editor and change all
strings that say CreateWindow into something like XCreatWindow
(It must be the same length to edit in the compiled form.)

Then you can write a function called CreateWindow that will
then call XCreatWindow.

hope this helps,

-- glen

[Keith Thompson]

glen herrmannsfeldt <ga*@ugcs.caltech.edu> writes:
[...]

Another way, though getting off of standard C, is to go through
the system library with a binary editor and change all
strings that say CreateWindow into something like XCreatWindow
(It must be the same length to edit in the compiled form.)

Then you can write a function called CreateWindow that will
then call XCreatWindow.

Of course, this may not work if the system library format includes
some kind of index or hash table.

--
Keith Thompson (The_Other_Keith) ks***@mib.org <http://www.ghoti.net/~kst>
San Diego Supercomputer Center <*> <http://www.sdsc.edu/~kst>
Schroedinger does Shakespeare: "To be *and* not to be"
(Note new e-mail address)

[August Derleth]

Kevin Goodsell <us*********************@neverbox.com> wrote in
news:r2****************@newsread2.news.pas.earthli nk.net on Wed 17 Dec
2003 01:00:23a:

Ali Akbar wrote:

Hi everyone,
I just wanted to know how my program can trap a particular API
call by windows.

Then you probably wanted a Windows programming group. This group is for
discussion of the C language as defined by the international C standard,
which has nothing to say about Windows or trapping APIs (whatever that
means).

-Kevin

<OT>
From what I understand, it means catching a call to an API (the hooks an
OS provides to application programs) so you can execute your code in
response to that call before the OS has a chance to do anything.

It is, of course, offtopic here.
</OT>

[Ben Pfaff]

al******@yahoo.com (Ali Akbar) writes:

I just wanted to know how my program can trap a particular API
call by windows. (The idea is that I want to hook all the open text
boxes and keep hooking new ones as and when they are created).

Your question is outside the domain of comp.lang.c, which discusses
only the standard C programming language, including the standard C
library. This is a remarkably narrow topic compared to what many
people expect.

For your convenience, the list below contains topics that are not
on-topic for comp.lang.c, and suggests newsgroups for you to
explore if you have questions about these topics. Please do
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