Re: XS malloc and free

[Courage]

from perldoc perlguts

    To free an SV that you've created, call "SvREFCNT_dec(SV*)". Norma
+lly
    this call is not necessary (see "Reference Counts and Mortality").

You do not free SV, you decrement its usage, and, when refcount goes to zero, it will be destroyed, and may be some destruction-time action will be activated

addition to free memory out from external library, consult that library's logic. Perl do not uses external char*, it will copy its data into newly created SV

[ikegami]

He's not asking about freeing the SV. He asking about freeing the string from which he created an SV.

Furthermore, SvREFCNT_dec should not be used here. Making the SV mortal (using sv_2mortal) will automatically free the SV at the end of the XSUB. Think of sv_2mortal as a delayed SvREFCNT_dec.