# Use Configuration Files

You can decrease the time you spend entering command-line options by using the configuration file to automate command-line entries. Configuration files are automatically processed every time you run the Intel® C++ Compiler Classic. You can insert any valid command-line options into the configuration file. The compiler processes options in the configuration file in the order in which they appear, followed by the specified command-line options when the compiler is invoked.

### Note

Options in the configuration file are executed every time you run the compiler. If you have varying option requirements for different projects, use Using Response Files .

## Sample Configuration Files

The default configuration files icc.cfg and icpc.cfg (Linux* and macOS) or or icl.cfg (Windows*), are located in the same directory as the compiler executable file. If you want to use a different configuration file than the default, you can use the ICCCFG/ICPCCFG (for Linux* and macOS) or ICLCFG (for Windows) environment variables to specify the location of another configuration file.

### Note

Anytime you instruct the compiler to use a different configuration file, the default configuration file(s) are ignored.

The following examples illustrate basic configuration files.

Linux

    ## Sample icpc.cfg file
      -I/my_headers

Windows

    ## Sample icl.cfg file
      /Ic:\my_headers

In the Windows examples, the compiler reads the configuration file and invokes the I option every time you run the compiler, along with any options specified on the command line.
Parent topic: Compilation

## See Also

Supported Environment Variables
Using Response Files