Appendix B. The Perl Debugger
The Perl symbolic debugger is invoked with perl -d. The command perl -de 0 is a good way to play with Perl and the debugger.
Upon startup, the debugger will try to read settings and initial commands from a file .perldb (perldb.ini on Windows) in the current directory or, if not found, in the home directory.
Any input to the debugger that is not one of the commands enumerated below is evaluated as a Perl expression.
a[ line ] commandSets an action for line.
A[ line ]Deletes the action at the given line; default is the current line. If line is
*, deletes all line actions.b[ line [ condition ] ]Sets a breakpoint at line; default is the current line.
bsubname [ condition ]Sets a breakpoint at the named subroutine.
b compilesubnameStops after the subroutine is compiled.
b loadfileSets a breakpoint at requireing the given file.
b postponesubname [ condition ]Sets a breakpoint at the first line of the subroutine after it is compiled.
B[ line ]Deletes the breakpoint at the given line; default is the current line. If line is
*, deletes all breakpoints.c[ line ]Continues (until line, or another breakpoint, or exit).
ffileSwitches to file and starts listing it.
hPrints out a long help message.
hcmdPrints out help for debugger command cmd.
h hPrints out a concise help message.
H[ -number ]Displays the last -number commands.
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 the next ...