The command assumes that the value of the specified String is a valid file name. It reads from that file until it ends or an Exit command is executed. If the end of the file is reached without ij exiting, reading will continue from the previous input source once the end of the file is reached. Files can contain additional Run commands.

ij prints out the statements in the file as it executes them.

Any changes made to the ij environment by the file are visible in the environment when processing resumes.