Using Debugger Commands

Command Formats Used with the Debugger

This section explains how formats are used to describe debugger command syntax. It also provides guidelines and constraints that are useful when you invoke the debugger, and a description of the various symbols used in commands.

Formats

Some commands consist of a single word, for example, exit. Others, such as print, can be issued as one word or with one or more arguments. Some command arguments can be nested. Given the possible length and complexity of the commands that are issued to the debugger, syntax descriptions do not show the complete syntax of the command in a single string. Rather, for commands that take many arguments, a separate prototype, or format, is created for each possible configuration of arguments.

For example, the syntax of the print command can appear in the following three formats:

Format 1: print

Format 2: print EXPRESSION

Format 3: print EXPRESSION [(PTYPE)][ %FMT] [COUNT][,EXPRESSION[(PTYPE)] [%FMT][COUNT]]

The following list gives typographical and syntax conventions:

The name of the command is print, as indicated by the lowercase, bold type.
Four different types of arguments can be used in several different combinations with the print command (EXPRESSION, PTYPE, %FMT, and COUNT). Arguments are indicated by uppercase letters. These arguments are described in Arguments in the Debugger Formats.
Several optional arguments can be used with the third format, as indicated by the square brackets.
The PTYPE argument must be enclosed in parentheses. The parentheses are part of the command syntax, as described in Command Symbols.

Command Directory shows the entire syntax of a command by presenting a series of formats that illustrate combinations of arguments, from simple to complex.

Guidelines

Command Directory is a detailed reference for all commands and command formats. It illustrates the syntax of debugger commands. The following guidelines apply to all command formats.

Format 1:	`print`
Format 2:	`print` EXPRESSION
Format 3:	`print` EXPRESSION [(PTYPE)][ %FMT] [COUNT][,EXPRESSION[(PTYPE)] [%FMT][COUNT]]

;	The semicolon separates multiple commands on a single line.
,	The comma separates arguments in commands, such as the `drop` and `print` commands.
{ }	Curly brackets surround commands in an `on` command.
( )	Parenthesis surround some arguments (such as a section name) in certain commands.
:	The colon is used in the following two contexts: It indicates a line number range. The first line in the range is on one side of the colon; the last line is on the other side, for example, 100:120. It indicates a variable in a function that is different from the function that you are in when the colon is preceded by a function name and followed by an identifier in expressions.
%	The percent sign indicates a print output format that is similar to the format specifier string of the `printf` function, when % is used in the `print` command and followed by a `printf` format specification. See print for more information.
\	The backslash is used as an escape symbol. It is used in the `print` command to escape the modulus operator (%) so that the debugger does not interpret % as a format marker, and in the `copy` and `whatis` commands with certain arguments it is used. Also, in line mode or when you are issuing commands from the Log window, you can use the backslash to continue a debugger command to a new line if it is the last character on the line.
*	The asterisk requests breakpoints or actions at hooks. See Default PF Key Commands for more information.
-	The minus sign indicates a relative direction toward the beginning of your source code. This symbol is used with the `list` command, and it has a different effect in line mode than it has in full-screen mode.
+	The plus sign indicates a relative direction toward the end of your source code. This symbol is used with the `list` command, and it has a different effect in line mode than it has in full-screen mode.