15.28 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.