It's then up to you to apply these patches, using something like
- # last=`ls -rt1 *.gz | tail -1`
+ # last=`ls -t *.gz | sed q`
# rsync -avz rsync://ftp.linux.activestate.com/perl-current-diffs/ .
# find . -name '*.gz' -newer $last -exec gzcat {} \; >blead.patch
# cd ../perl-current
to L<perlguts/Background and PERL_IMPLICIT_CONTEXT> for information on
the C<[pad]THX_?> macros.
-
=head2 Poking at Perl
To really poke around with Perl, you'll probably want to build Perl for
This binary is used in place of the standard 'perl' binary
when you want to debug Perl memory problems.
+To minimize the number of memory leak false alarms
+(see L</PERL_DESTRUCT_LEVEL>), set environment variable
+PERL_DESTRUCT_LEVEL to 2.
+
+ setenv PERL_DESTRUCT_LEVEL 2
+
+In Bourne-type shells:
+
+ PERL_DESTRUCT_LEVEL=2
+ export PERL_DESTRUCT_LEVEL
+
As an example, to show any memory leaks produced during the
standard Perl testset you would create and run the Purify'ed
perl as:
environment variable PERL_DESTRUCT_LEVEL to a non-zero value.
The t/TEST wrapper does set this to 2, and this is what you
need to do too, if you don't want to see the "global leaks":
+For example, for "third-degreed" Perl:
- PERL_DESTRUCT_LEVEL=2 ./perl.third t/foo/bar.t
+ env PERL_DESTRUCT_LEVEL=2 ./perl.third -Ilib t/foo/bar.t
=head2 Profiling
For further information, see your system's manual pages for pixie and prof.
+=head2 Miscellaneous tricks
+
+=over 4
+
+=item *
+
+Those debugging perl with the DDD frontend over gdb may find the
+following useful:
+
+You can extend the data conversion shortcuts menu, so for example you
+can display an SV's IV value with one click, without doing any typing.
+To do that simply edit ~/.ddd/init file and add after:
+
+ ! Display shortcuts.
+ Ddd*gdbDisplayShortcuts: \
+ /t () // Convert to Bin\n\
+ /d () // Convert to Dec\n\
+ /x () // Convert to Hex\n\
+ /o () // Convert to Oct(\n\
+
+the following two lines:
+
+ ((XPV*) (())->sv_any )->xpv_pv // 2pvx\n\
+ ((XPVIV*) (())->sv_any )->xiv_iv // 2ivx
+
+so now you can do ivx and pvx lookups or you can plug there the
+sv_peek "conversion":
+
+ Perl_sv_peek(my_perl, (SV*)()) // sv_peek
+
+(The my_perl is for threaded builds.)
+Just remember that every line, but the last one, should end with \n\
+
+Alternatively edit the init file interactively via:
+3rd mouse button -> New Display -> Edit Menu
+
+Note: you can define up to 20 conversion shortcuts in the gdb
+section.
+
+=back
+
=head2 CONCLUSION
We've had a brief look around the Perl source, an overview of the stages