io: keep path instead of getting path from file descriptor or handle
io: keep path instead of getting path from file descriptor or handle

It's for portability.

kenhys/groonga,komainu8/groonga,groonga/groonga,groonga/groonga,groonga/groonga,groonga/groonga,kenhys/groonga,komainu8/groonga,kenhys/groonga,komainu8/groonga,kenhys/groonga,komainu8/groonga,komainu8/groonga,groonga/groonga,komainu8/groonga,kenhys/groonga,komainu8/groonga,kenhys/groonga,groonga/groonga,kenhys/groonga,komainu8/groonga,groonga/groonga,groonga/groonga,kenhys/groonga