Most character or data pointers in C cannot be used just as such in perl. They will have to be converted to a SCALAR value

The nice thing about Inline::C is that it should take care of this, i.e. the necessary .xs (and .c) code doing the conversions is created behind the scenes - at least for simple types such as char*.

For example, the following function returning a char* is mapped to a normal scalar on the Perl side: 

#!/usr/bin/perl

use Inline C => Config => BUILD_NOISY => 1, CLEAN_AFTER_BUILD => 0;
use Inline C => <<'END_OF_C_CODE';

char* GetImage() {

    char *data = "test-test-test";

    return(data);
}
END_OF_C_CODE


my $data = GetImage();

print "$data\n";    # "test-test-test"

[download]

(btw, the CLEAN_AFTER_BUILD => 0 option I've specified above is very useful when you want to look at the auto-generated XS/C wrapper code for debugging purposes)

So, if the data as returned by the OP's GetImage() function is in fact char*, things should just work fine in this regard. In other words, I suspect the problem lies elsewhere...

In reply to Re^2: Open CV problem by Anonyrnous Monk
in thread Open CV problem by russellp

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