When editing C/C++ files, Source Insight can perform symbol completion for the standard libraries, such as the C-runtime, STL, WinAPI, or any other library such as Boost. This is accomplished by importing symbols from the C/C++ files and header files on your machine.
To import the C/C++ runtime symbols, use the Project > Import External Symbols command, or use the Preferences: Symbol Lookups dialog box and click the Import Symbols button.
To import C/C++ runtime symbols:
1.In the Options > Preferences: Symbol Lookups dialog box, click the Import Symbols button.
2.In the Import External Symbols dialog box, click on the Add... button. If you already have an INCLUDE path environment variable, then click on Import from an INCLUDE path. Otherwise, you can click on Import from a source code tree and navigate to the directory that contains the runtime library include files.
3.The directories will be scanned and symbol declarations will be extracted into a special project called an import library. This may take a few minutes depending on the number of file encountered.
Now, auto-complete should work for the symbols that are defined in the header files.