Passes the following command to the host operating system.

Introduces a comment line.

Defines, undefines, or lists aliases. It enables you to define your own symbolic debugger commands.

Writes a message to stderr.

Displays a list of available commands, or help on a particular command.

Sends the output of subsequent commands to a file in addition to the screen.

Executes a set of debugger commands which have previously been stored in a file, as if they are being typed at the keyboard.

Examines the contents of variables in the program being debugged.

Types the contents of a source file, or any text file, between a specified pair of line numbers.

Is part of a multi-statement line.

Terminates the current symbolic debugger session and closes any open log or obey files.