i am using Dev-c++ editor and it uses gcc compiler. I gave an instruction system("PAUSE"); This is obviously a linux command, but i am giving it in windows. What windows API will this instruction call into. How to find them and how to decode the object files.
The C "system" function asks the host operating system to execute the specified command, so system("PAUSE") should do whatever your operating system normally does when you run the "PAUSE" command. In Windows, it probably calls the "system" function in msvcrt.dll.
I'm not sure what you mean by "decode the object files". If you want to see the assembler source code for your compiled C function, run gcc with the -S option.