Why, given that SV *a is created in the Perl code and is not going out of scope, do I have to increment the ref count when I return it to Perl

Not sure how to answer that question either ... hope the following helps: 
use warnings;
use Inline C => Config =>
    CLEAN_AFTER_BUILD => 0,
    BUILD_NOISY => 1;

use Inline C => <<'EOC';

SV * foo1(SV * a) {
     SV * c = newSVsv(a);
     return c;
}

SV * foo2(SV * a) {
     return SvREFCNT_inc(a);
}

EOC

$x = 'hello';
print foo1($x);
print foo1(" world\n");
print foo2($x);
print foo2(" world\n");

__END__

D:\pscrpt\inline>perl try.pl
hello world
hello world

[download]

Cheers,
Rob

In reply to Re: XS/Inline::C concat *any* two SVs. by syphilis
in thread XS/Inline::C concat *any* two SVs. by BrowserUk

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