17 lines
626 B
Text
17 lines
626 B
Text
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B::COW provides some naive additional B helpers to check the COW
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status of one SvPV. COW or Copy On Write introduction
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A COWed SvPV is sharing its string (the PV) with other SvPVs. It's a
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(kind of) Read Only C string, that would be Copied On Write (COW).
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More than one SV can share the same PV, but when one PV need to alter
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it, it would perform a copy of it, decrease the COWREFCNT counter.
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One SV can then drop the COW flag when it's the only one holding a
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pointer to the PV.
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The COWREFCNT is stored at the end of the PV, after the the "\0".
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That value is limited to 255, when we reach 255, a new PV would be
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created,
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