reading through a file

when people post files on this site, other people always wanna know or it is safe
but an antivirus check doesn't always work since your antivirus considers bots and hacks almost always as a virus /trojan

and then people say, it's safe, i read through it
but now i wonder how can you see the source of the program?
how can i check it by myself
because i got yesterday a big virus from a fake sibibot

You can decompile an exe, to see the source (not easy to do in most cases) or you can use a virtual machine and a network monitor/sniffer to see whats coming in and whats going out while running the application.

You won't see the actual source, you will see the the machine code. It depends on the language the app has been compiled with, if the app uses .NET then you can see most of the source pretty clearly with ".NET Reflector ( [Only registered and activated users can see links. Click Here To Register...] " ). Though if the application has been compiled w/o any usage of .NET theres no way to get access to the actual source. To answer your question, AV's are mostly right, and mostly false. There is no 100% guarantee that the application is clean even if the AV says it is, it still doesn't mean that it is. It's simple, don't simply download/run applications from random sources, but if you feel that you must test them then use [Only registered and activated users can see links. Click Here To Register...].. in the end you just shouldn't download from random sources. ;)