* agent/gpg-agent.c (handle_connections): It's for POSIX.
* kbx/keyboxd.c (handle_connections): Ditto.
* scd/app.c (handle_connections): Ditto.
* scd/scdaemon.c (handle_connections): Ditto.
tpm2d/tpm2daemon.c (handle_connections): Ditto.
* tests/gpgscm/ffi.c (do_pipe): Use GNUPG_PIPE_BOTH.
(do_inbound_pipe): Use GNUPG_PIPE_INBOUND.
(do_outbound_pipe): Use GNUPG_PIPE_OUTBOUND.
* common/call-gpg.c (_gpg_encrypt): Specify outbound and inbound.
(_gpg_decrypt): Likewise.
* common/exechelp-posix.c (gnupg_create_pipe): Add an argument.
* common/exechelp-w32.c (create_pipe_and_estream): Care about
how PIPE handles are inherited to child process.
(gnupg_create_pipe): Add an argument.
* common/exechelp.h: Add enum values.