in reply to Re: Need to pass an unsigned char array from an xsub back to Perl
in thread Need to pass an unsigned char array from an xsub back to Perl

Or, if you want to use PPCODE: 
void
GenerateSessionID()
    PREINIT:
        char uuid[16];
    PPCODE:
        XSessionID((uuid_t*)uuid);
        ST(0) = newSVpvn(uuid, 16);
        sv_2mortal(ST(0));
        XSRETURN(1);

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 Thats quite bloated. This is less bloated. 
void
GenerateSessionID()
    PREINIT:
        char uuid[16] = {0); //zero fill
    PPCODE:
        XSessionID((uuid_t*)uuid);
        PUSHs(sv_2mortal((newSVpvn(uuid, 16)));

[download]
Also the OP might want to zero his UUID since we are not checking the return value of XSessionID to determine failure.

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