read from .ini

I am a newbie on scripting, i tried to read from an .ini file and i am not shure how to do this could anyone help me?
Here is what i tried with.

• ; On initialization
  Function .onInit
  
  !insertmacro MUI_LANGDLL_DISPLAY
  
  ReadINIStr $ini_value "$INSTDIR\sqltalk.ini" "Input Font" "Weight"
  StrCmp $ini_value "700" +1 +2
  MessageBox MB_OK "Nu du"
  FunctionEnd

My thougth is, if $ini_value is equal with 700 the messagebox would pop up.

What is the problem? Did you declare that variable?

When i create the installation file i want to send a ini-file with the installation package. It contains a serialnumber, witch is unique for every installation. When the istaller runs I want to read out the serialnumber and write it to the register.

The code in the earlier message was a trie to se if it was reading the file.

Sorry for my bad english