The -r command line switch is used to run the built-in debugger without creating a database in advance. The format is this switch is:

The explanation of the fields:

All fields except the first one are optional. Also, the pid field can be specified as '+'. IDA will display the process list to attach. See examples below for typical command lines:

When the -r switch is used, IDA works with the databases in the following way:

The rest of the command line is passed to the launched process.

In the case there is no input file (when attaching to an existing process, for example), then the temporary database is created in the standard temporary directory. For Windows, this directory is usually "Local Setting\Temp" in the user profile directory.