use strict;
use warnings;
use Devel::Peek;

use Inline C =><<'EOC';

void foo(SV * buffer) {
  char *data = "Hello there";
  sv_setpv(buffer, data);
}

void bar(unsigned char * buffer) {
  buffer[49] = 65;
}

void _set_CUR(SV * buffer, int bytes) {
  SvCUR_set(buffer, bytes);
}

EOC

my $buffer = 'z' x 60;
Dump $buffer;
foo($buffer);
Dump $buffer;

bar($buffer);
_set_CUR($buffer, 60); # Ensure that Devel::Peek::Dump will display all 60 bytes.
Dump $buffer;