How to use win32 CreateProcess function to wait until the child done to write to file

Hello
im not win32 programmer and its all new to me. i like to open process from my parent win32 application ( ok this is i know how to do) the child process then write to text file and close it self . how can i detect in the parent application that the child application done writing to the text file . and then from the parent app to read the text file . this is all in win32 c++ Thanks

If the child process exits right after write file is completed then you can use WaitForSingleObject to wait for the child process handle (it is seet by CreateProcess and saved in lpProcessInformation parameter)

thank you very much for your answer , can you please point me to some simple examples?

Sure!
Just begin with the CreateProcess Function and WaitForSingleObject Function documentation.
Under CreateProcess docs you'll also find some examples...