Devel::PPPort - Perl/Pollution/Portability Devel::PPPort::WriteFile(); # defaults to ./ppport.h Devel::PPPort::WriteFile('someheader.h'); Perl's API has changed over time, gaining new features, new functions, increasing its flexibility, and reducing the impact on the C namespace environment (reduced pollution). The header file written by this module, typically ppport.h, attempts to bring some of the newer Perl API features to older versions of Perl, so that you can worry less about keeping track of old releases, but users can still reap the benefit. "Devel::PPPort" contains a single function, called "WriteFile". Its only purpose is to write the ppport.h C header file. This file contains a series of macros and, if explicitly requested, functions that allow XS modules to be built using older versions of Perl. Currently, Perl versions from 5.003 to 5.9.2 are supported. This module is used by "h2xs" to write the file ppport.h.

Why use ppport.h?
You should use ppport.h in modern code so that your code will work with the widest range of Perl interpreters possible, without significant additional work. You should attempt older code to fully use ppport.h, because the reduced pollution of newer Perl versions is an important thing. It's so important that the old polluting ways of original Perl modules will not be supported very far into the future, and your module will almost certainly break! By adapting to it now, you'll gain compatibility and a sense of having done the electronic ecology some good.

How to use ppport.h
Don't direct the users of your module to download "Devel::PPPort". They are most probably no XS writers. Also, don't make ppport.h optional. Rather, just take the most recent copy of ppport.h that you can find (e.g. by generating it with the latest "Devel::PPPort" release from CPAN), copy it into your project, adjust your project to use it, and distribute the header along with your module.

Running ppport.h
But ppport.h is more than just a C header. It's also a Perl script that can check your source code. It will suggest hints and portability notes, and can even make suggestions on how to change your code. You can run it like any other Perl program: perl ppport.h It also has embedded documentation, so you can use perldoc ppport.h to find out more about how to use it.

WriteFile
"WriteFile" takes one optional argument. When called with one argument, it expects to be passed a filename. When called with no arguments, it defaults to the filename ppport.h. The function returns a true value if the file was written successfully. Otherwise it returns a false value. ppport.h supports Perl versions from 5.003 to 5.9.2 in threaded and non-threaded configurations.

Provided Perl compatibility API
The header file written by this module, typically ppport.h, provides access to the following elements of the Perl API that is not available in older Perl releases: _aMY_CXT _pMY_CXT aMY_CXT aMY_CXT_ aTHX aTHX_ AvFILLp boolSV call_argv call_method call_pv call_sv CopFILE CopFILE_set CopFILEAV CopFILEGV CopFILEGV_set CopFILESV CopSTASH CopSTASH_eq CopSTASH_set CopSTASHPV CopSTASHPV_set CopyD dAX DEFSV dITEMS dMY_CXT dMY_CXT_SV dNOOP dTHR dTHX dTHXa dTHXoa dUNDERBAR END_EXTERN_C ERRSV eval_pv eval_sv EXTERN_C get_av get_cv get_hv get_sv grok_bin grok_hex grok_number GROK_NUMERIC_RADIX grok_numeric_radix grok_oct gv_stashpvn IN_LOCALE IN_LOCALE_COMPILETIME IN_LOCALE_RUNTIME IN_PERL_COMPILETIME INT2PTR IS_NUMBER_GREATER_THAN_UV_MAX IS_NUMBER_IN_UV IS_NUMBER_INFINITY IS_NUMBER_NAN IS_NUMBER_NEG IS_NUMBER_NOT_INT IVdf IVSIZE IVTYPE memEQ memNE MoveD mPUSHi mPUSHn mPUSHp mPUSHu mXPUSHi mXPUSHn mXPUSHp mXPUSHu MY_CXT MY_CXT_CLONE MY_CXT_INIT newCONSTSUB newRV_inc newRV_noinc newSVpvn newSVuv NOOP NUM2PTR NVef NVff NVgf NVTYPE PERL_BCDVERSION PERL_GCC_BRACE_GROUPS_FORBIDDEN PERL_INT_MAX PERL_INT_MIN PERL_LONG_MAX PERL_LONG_MIN PERL_MAGIC_arylen PERL_MAGIC_backref PERL_MAGIC_bm PERL_MAGIC_collxfrm PERL_MAGIC_dbfile PERL_MAGIC_dbline PERL_MAGIC_defelem PERL_MAGIC_env PERL_MAGIC_envelem PERL_MAGIC_ext PERL_MAGIC_fm PERL_MAGIC_glob PERL_MAGIC_isa PERL_MAGIC_isaelem PERL_MAGIC_mutex PERL_MAGIC_nkeys PERL_MAGIC_overload PERL_MAGIC_overload_elem PERL_MAGIC_overload_table PERL_MAGIC_pos PERL_MAGIC_qr PERL_MAGIC_regdata PERL_MAGIC_regdatum PERL_MAGIC_regex_global PERL_MAGIC_shared PERL_MAGIC_shared_scalar PERL_MAGIC_sig PERL_MAGIC_sigelem PERL_MAGIC_substr PERL_MAGIC_sv PERL_MAGIC_taint PERL_MAGIC_tied PERL_MAGIC_tiedelem PERL_MAGIC_tiedscalar PERL_MAGIC_utf8 PERL_MAGIC_uvar PERL_MAGIC_uvar_elem PERL_MAGIC_vec PERL_MAGIC_vstring PERL_QUAD_MAX PERL_QUAD_MIN PERL_REVISION PERL_SCAN_ALLOW_UNDERSCORES PERL_SCAN_DISALLOW_PREFIX PERL_SCAN_GREATER_THAN_UV_MAX PERL_SCAN_SILENT_ILLDIGIT PERL_SHORT_MAX PERL_SHORT_MIN PERL_SUBVERSION PERL_UCHAR_MAX PERL_UCHAR_MIN PERL_UINT_MAX PERL_UINT_MIN PERL_ULONG_MAX PERL_ULONG_MIN PERL_UNUSED_DECL PERL_UQUAD_MAX PERL_UQUAD_MIN PERL_USHORT_MAX PERL_USHORT_MIN PERL_VERSION PL_compiling PL_copline PL_curcop PL_curstash PL_DBsingle PL_DBsub PL_debstash PL_defgv PL_diehook PL_dirty PL_dowarn PL_errgv PL_hexdigit PL_hints PL_na PL_no_modify PL_perl_destruct_level PL_perldb PL_ppaddr PL_rsfp PL_rsfp_filters PL_stack_base PL_stack_sp PL_stdingv PL_Sv PL_sv_arenaroot PL_sv_no PL_sv_undef PL_sv_yes PL_tainted PL_tainting pMY_CXT pMY_CXT_ Poison pTHX pTHX_ PTR2IV PTR2NV PTR2ul PTR2UV PTRV PUSHmortal PUSHu SAVE_DEFSV START_EXTERN_C START_MY_CXT STMT_END STMT_START sv_2pv_nolen sv_2pvbyte sv_2uv sv_catpv_mg sv_catpvf_mg sv_catpvf_mg_nocontext sv_catpvn_mg sv_catpvn_nomg sv_catsv_mg sv_catsv_nomg sv_pvn sv_pvn_force sv_pvn_nomg sv_setiv_mg sv_setnv_mg sv_setpv_mg sv_setpvf_mg sv_setpvf_mg_nocontext sv_setpvn_mg sv_setsv_mg sv_setsv_nomg sv_setuv sv_setuv_mg sv_usepvn_mg sv_uv sv_vcatpvf sv_vcatpvf_mg sv_vsetpvf sv_vsetpvf_mg SvGETMAGIC SvIV_nomg SvPV_force_nomg SvPV_nolen SvPV_nomg SvPVbyte SvUV SvUV_nomg SvUVX SvUVx SvUVXx UNDERBAR UVof UVSIZE UVTYPE UVuf UVXf UVxf vnewSVpvf XPUSHmortal XPUSHu XSRETURN_UV XST_mUV ZeroD

Perl API not supported by ppport.h
There is still a big part of the API not supported by ppport.h. Either because it doesn't make sense to back-port that part of the API, or simply because it hasn't been implemented yet. Patches welcome! Here's a list of the currently unsupported API, and also the version of Perl below which it is unsupported: SvPVbyte_force find_rundefsvoffset vnormal hv_assert hv_clear_placeholders hv_scalar scan_version sv_2iv_flags sv_2uv_flags new_version save_set_svflags upg_version vcmp vnumify vstringify SvIsCOW SvIsCOW_shared_hash SvVOK doing_taint is_utf8_string_loc packlist save_bool savestack_grow_cnt scan_vstring sv_cat_decode sv_compile_2op sv_setpviv sv_setpviv_mg unpackstring hv_iternext_flags hv_store_flags is_utf8_idcont nothreadhook PerlIO_clearerr PerlIO_close PerlIO_eof PerlIO_error PerlIO_fileno PerlIO_fill PerlIO_flush PerlIO_get_base PerlIO_get_bufsiz PerlIO_get_cnt PerlIO_get_ptr PerlIO_read PerlIO_seek PerlIO_set_cnt PerlIO_set_ptrcnt PerlIO_setlinebuf PerlIO_stderr PerlIO_stdin PerlIO_stdout PerlIO_tell PerlIO_unread PerlIO_write SvLOCK SvSHARE SvUNLOCK atfork_lock atfork_unlock custom_op_desc custom_op_name deb debstack debstackptrs gv_fetchmeth_autoload ibcmp_utf8 my_fork my_socketpair pack_cat perl_destruct pv_uni_display regclass_swash save_shared_pvref savesharedpv sortsv sv_copypv sv_magicext sv_nolocking sv_nosharing sv_nounlocking sv_recode_to_utf8 sv_uni_display to_uni_fold to_uni_lower to_uni_title to_uni_upper to_utf8_case to_utf8_fold to_utf8_lower to_utf8_title to_utf8_upper unpack_str uvchr_to_utf8_flags uvuni_to_utf8_flags vdeb calloc getcwd_sv init_tm malloc mfree mini_mktime my_atof2 my_strftime op_null realloc sv_2pv_flags sv_catpvn_flags sv_catsv_flags sv_pvn_force_flags sv_setsv_flags sv_utf8_upgrade_flags swash_fetch POPpbytex SvUOK bytes_from_utf8 csighandler despatch_signals do_openn gv_handler is_lvalue_sub my_popen_list newSVpvn_share save_mortalizesv save_padsv scan_num sv_force_normal_flags sv_setref_uv sv_unref_flags sv_utf8_upgrade utf8_length utf8_to_uvchr utf8_to_uvuni utf8n_to_uvchr utf8n_to_uvuni uvchr_to_utf8 uvuni_to_utf8 apply_attrs_string bytes_to_utf8 gv_efullname4 gv_fullname4 is_utf8_string save_generic_pvref utf16_to_utf8 utf16_to_utf8_reversed utf8_to_bytes SvIOK_UV SvIOK_notUV SvIOK_only_UV SvPOK_only_UTF8 SvPVbyte_nolen SvPVbytex SvPVbytex_force SvPVutf8 SvPVutf8_force SvPVutf8_nolen SvPVutf8x SvPVutf8x_force SvUTF8 SvUTF8_off SvUTF8_on av_delete av_exists call_atexit cast_i32 cast_iv cast_ulong cast_uv do_gv_dump do_gvgv_dump do_hv_dump do_magic_dump do_op_dump do_open9 do_pmop_dump do_sv_dump dump_all dump_eval dump_form dump_indent dump_packsubs dump_sub dump_vindent get_context get_ppaddr gv_dump init_i18nl10n init_i18nl14n is_uni_alnum is_uni_alnum_lc is_uni_alnumc is_uni_alnumc_lc is_uni_alpha is_uni_alpha_lc is_uni_ascii is_uni_ascii_lc is_uni_cntrl is_uni_cntrl_lc is_uni_digit is_uni_digit_lc is_uni_graph is_uni_graph_lc is_uni_idfirst is_uni_idfirst_lc is_uni_lower is_uni_lower_lc is_uni_print is_uni_print_lc is_uni_punct is_uni_punct_lc is_uni_space is_uni_space_lc is_uni_upper is_uni_upper_lc is_uni_xdigit is_uni_xdigit_lc is_utf8_alnum is_utf8_alnumc is_utf8_alpha is_utf8_ascii is_utf8_char is_utf8_cntrl is_utf8_digit is_utf8_graph is_utf8_idfirst is_utf8_lower is_utf8_mark is_utf8_print is_utf8_punct is_utf8_space is_utf8_upper is_utf8_xdigit load_module magic_dump mess my_atof my_fflush_all newANONATTRSUB newATTRSUB newMYSUB newPADOP newXS newXSproto new_collate new_ctype new_numeric op_dump perl_parse pmop_dump pv_display re_intuit_start re_intuit_string reginitcolors require_pv safesyscalloc safesysfree safesysmalloc safesysrealloc save_I8 save_alloc save_destructor save_destructor_x save_re_context save_vptr scan_bin set_context set_numeric_local set_numeric_radix set_numeric_standard str_to_version sv_2pvutf8 sv_2pvutf8_nolen sv_force_normal sv_len_utf8 sv_pos_b2u sv_pos_u2b sv_pv sv_pvbyte sv_pvbyten sv_pvbyten_force sv_pvutf8 sv_pvutf8n sv_pvutf8n_force sv_rvweaken sv_utf8_decode sv_utf8_downgrade sv_utf8_encode swash_init tmps_grow to_uni_lower_lc to_uni_title_lc to_uni_upper_lc utf8_distance utf8_hop vcroak vform vload_module vmess vwarn vwarner warner POPpx get_vtbl save_generic_svref PL_modglobal cx_dump debop debprofdump fbm_compile fbm_instr get_op_descs get_op_names init_stacks mg_length mg_size newHVhv new_stackinfo regdump regexec_flags regnext runops_debug runops_standard save_hints save_iv save_threadsv screaminstr sv_iv sv_nv sv_peek sv_true do_binmode save_aelem save_helem newWHILEOP GIMME_V G_VOID HEf_SVKEY HeHASH HeKEY HeKLEN HePV HeSVKEY HeSVKEY_force HeSVKEY_set HeVAL SvSetMagicSV SvSetMagicSV_nosteal SvSetSV_nosteal SvTAINTED SvTAINTED_off SvTAINTED_on block_gimme call_list cv_const_sv delimcpy do_open form gv_autoload4 gv_efullname3 gv_fetchmethod_autoload gv_fullname3 hv_delayfree_ent hv_delete_ent hv_exists_ent hv_fetch_ent hv_free_ent hv_iterkeysv hv_ksplit hv_store_ent ibcmp_locale my_failure_exit my_memcmp my_pclose my_popen newSVpvf rsignal rsignal_state save_I16 save_gp start_subparse sv_catpvf sv_catpvf_mg sv_cmp_locale sv_derived_from sv_gets sv_setpvf sv_setpvf_mg sv_taint sv_tainted sv_untaint sv_vcatpvf sv_vcatpvf_mg sv_vcatpvfn sv_vsetpvf sv_vsetpvf_mg sv_vsetpvfn unsharepvn vnewSVpvf If you find any bugs, "Devel::PPPort" doesn't seem to build on your system or any of its tests fail, please use the CPAN Request Tracker at <http://rt.cpan.org/> to create a ticket for the module. Version 1.x of Devel::PPPort was written by Kenneth Albanowski. Version 2.x was ported to the Perl core by Paul Marquess. Version 3.x was ported back to CPAN by Marcus Holland-Moritz. Version 3.x, Copyright (C) 2004, Marcus Holland-Moritz. Version 2.x, Copyright (C) 2001, Paul Marquess. Version 1.x, Copyright (C) 1999, Kenneth Albanowski. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See h2xs, ppport.h.