about IDA

[Felheart]

Hi there,
i have few questions about IDA Pro.

1) I made a (very) small tool and compiled it in release mode (VS2010)
The exe is 49KB big.
When I decompile the exe with IDA there are some functions I don't recognize.
For example a function that is 0x1004 bytes long (the biggest function in the exe).
The function is very complex and doesn't call any APIs so I could guess what it is doing.

Screen:
3670

Is there a way to find how from which file the compiler made this function?
How do I know what this function is doing?

2)
How can I edit assembly code in IDA like in Olly ?
Can I only assemble/change something while debugging it with IDA? If so, how ?

3)
And where do the 200+ functions in my exe come from?
The original .cpp file (the only source file the program consists of) only contains 3 functions (main, dialogproc, a threadfunction).

Thanks

[learn_more]

crt runtime maybe?

[kingorgy96]

why not reading the faq/readme from ida?

[bobbysing]

I'm pretty sure neither of his questions is answered appropriately by the IDA documentation.

1. Compile your application with debug information and IDA will tell you what method that is
2. IDA is meant to be used for static binary analysis, you can't edit the code like you can in OllyDbg. ( There are IDC methods to patch bytes in your IDA database. )
3. What learn_more said