I want to set the build directory "_Inline" to some other path

I usually do this by setting the Inline config option "DIRECTORY" to the desired location.
This requires that the specified directory already exists.
It would also involve amending the code inside JavaScript:::DukTape ... I'm not sure if that's what you want.

use warnings;

use Inline C => Config =>
  # C:/inline_build must already exist
  DIRECTORY => 'C:/inline_build',
;

use Inline C =><<'EOC';

void foo() {
 printf("Hello World\n");
}

EOC

foo();
[download]

Cheers,
Rob