I was sad to see that Inline::C's documentation doesn't even really hint at what happens if your C function returns a value of type "char*".

If you find your ExtUtils/typemap file you'll find the following lines (not together): 

char *            T_PV
INPUT
T_PV
    $var = ($type)SvPV_nolen($arg)
OUTPUT
T_PV
    sv_setpv((SV*)$arg, $var);

[download]

so returning a "char*" calls sv_setpv(). If you read perlguts you'll see a disappointingly vague hint that sv_setpv() sets the length of the scalar's string value based on strlen(str), which isn't appropriate for your "binary" string.

So you instead want to return a SV* type of value and (again, it is sad here that Inline::C doesn't even show how to do this) use something more like return svNEWpvn( str, len );.

So now you also have several places that could use documentation patches. /:

- tye        

In reply to Re: keeping binary data raw (char*) by tye
in thread keeping binary data raw by downer

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