I was unsure if this was the best location for this question, but I saw no better place...

Working with Libnet to make a perl interface ala XS I came across this function prototype:

int libnet_init_packet(size_t p_size, u_char **buf);<br><br>

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This function essentially is a wrapper to malloc and passes back the pointer by reference. I assumed this is what i ought to put in my typemap:

u_char **    T_PV

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Then in my XS file:

int
libnet_init_packet(p_size, buf)
        size_t p_size
        u_char & * buf
    OUTPUT:
        buf

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However, I try to make this and I get an error at "u_char & * buf". Shouldn't this work? If no, how can I manage around this? Simply assume the value I pass from Perl holds a pointer and pass it in as a reference then possibly have something like this in my XS file?

int
libnet_init_packet(p_size, buf)
        size_t p_size
        void & buf
    OUTPUT:
        buf

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The obvious typecasting issues aside, this seems like it might work. Your help is sincerely appreciated it. BTW, this is my first XS project. Thanks!

In reply to XS question: typemap for a pointer to a pointer? by Big Willy

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