in reply to threads::shared locking via C API

The function you need to call is Perl_sharedsv_locksv(pTHX_ SV *sv) found in threads::shared.xs.

But good luck in working out how to link to it.

Another mystery that has long defeated me is quite where the perl-level lock() function (keyword or operator) lives and how it gets translated into a call to the above.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

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Re^2: threads::shared locking via C API
by Anonymous Monk on Aug 26, 2011 at 07:57 UTC
[reply]
[d/l]

      Yes, thanks. But that doesn't get you very far. 

      c:\test\perl-5.14.0-RC1>findstr SvLOCK *.?
pp.c:    SvLOCK(sv);
sv.h:=for apidoc Am|void|SvLOCK|SV* sv
sv.h:#define SvLOCK(sv) PL_lockhook(aTHX_ sv)

c:\test\perl-5.14.0-RC1>findstr PL_lockhook *.?
embedvar.h:#define PL_lockhook          (vTHX->Ilockhook)
embedvar.h:#define PL_Ilockhook         PL_lockhook
sv.c:    PL_lockhook            = proto_perl->Ilockhook;
sv.h:#define SvLOCK(sv) PL_lockhook(aTHX_ sv)

c:\test\perl-5.14.0-RC1>findstr Ilockhook *.?
embedvar.h:#define PL_lockhook          (vTHX->Ilockhook)
embedvar.h:#define PL_Ilockhook         PL_lockhook
intrpvar.h:PERLVARI(Ilockhook,  share_proc_t,   Perl_sv_nosharing)
sv.c:    PL_lockhook            = proto_perl->Ilockhook;

      [download]

      The whole 'lock locks the variable if threading is enable but is a silent noop otherwise', is the single most pointless piece of logic ever. (After the over-elaborate feature mechanism that is.)

      Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
      "Science is about questioning the status quo. Questioning authority".
      In the absence of evidence, opinion is indistinguishable from prejudice.
[reply]
[d/l]

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