The Perl Debugger

The Perl symbolic debugger is invoked with perl -d.

• h
• Prints out a help message.
• T
• Prints a stack trace.
• s
• Single steps.
• n
• Single steps around subroutine call.
• [RETURN]
• Repeats last s or n.
• r
• Returns from the current subroutine.
• c [ line ]
• Continues (until line, or another breakpoint, or exit).
• p expr
• Prints expr.
• l [ range ]
• Lists a range of lines. range may be a number, start-end, start+amount, or a subroutine name. If range is omitted, lists next window.
• w
• Lists window around current line.
• -
• Lists previous window.
• f file
• Switches to file and starts listing it.
• l sub
• Lists the named subroutine.
• S
• Lists the names of all subroutines.
• /pattern/
• Searches forward for pattern.
• ?pattern?
• Searches backward for pattern.
• b [ line [ condition ]]
• Sets breakpoint at line ; default is the current line.
• b sub [ condition ]
• Sets breakpoint at the subroutine.
• d [ line ]
• Deletes breakpoint at the given line.
• D
• Deletes all breakpoints.
• L
• Lists lines that have breakpoints or actions.
• a line command
• Sets an action for line.
• A
• Deletes all line actions.
• < command
• Sets an action to be executed before every debugger prompt.
• > command
• Sets an action to be executed before every s, c, or n command.
• V [ package [ vars ] ]
• Lists all variables in a package. Default package is main.
• X [ vars ]
• Like V, but assumes current package.
• ! [ [-]number ]
• Re-executes a command. Default is the previous command.
• H [ -number ]
• Displays the last -number commands of more than one letter.
• t
• Toggles trace mode.
• = [ alias value ]
• Sets alias, or lists current aliases.
• q
• Quits. You may also use your EOF character.
• command
• Executes command as a Perl statement.