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=head1 NAME
nbdkit_stdio_safe - is it safe to interact with stdin and stdout
=head1 SYNOPSIS
#include <nbdkit-plugin.h>
int nbdkit_stdio_safe (void);
=head1 DESCRIPTION
The C<nbdkit_stdio_safe> utility function returns whether or not it is
safe to interact with stdin and stdout during the configuration phase.
This is needed because when the nbdkit I<-s> option is used the plugin
must not directly interact with stdin, because that would interfere
with network communication.
The result of this function only matters in callbacks up to
C<.config_complete>. Once nbdkit reaches C<.get_ready>, the plugin
should assume that nbdkit may have closed the original stdin and
stdout in order to become a daemon.
L<nbdkit-sh-plugin(3)> uses this function to determine whether it is
safe to support C<script=-> to read a script from stdin. Also
constructs like C<password=-> (see L<nbdkit_read_password(3)>) are
disabled when reading from stdio is not safe.
=head1 RETURN VALUE
The function returns C<1> (safe) or C<0> (not safe).
It cannot return an error.
=head1 LANGUAGE BINDINGS
In L<nbdkit-ocaml-plugin(3)>:
NBDKit.stdio_safe : unit -> bool
In L<nbdkit-python-plugin(3)>:
import nbdkit
is_safe = nbdkit.stdio_safe()
In L<nbdkit-rust-plugin(3)>:
use nbdkit::*;
pub fn is_stdio_safe() -> bool
=head1 HISTORY
C<nbdkit_stdio_safe> was added in nbdkit 1.20.
=head1 SEE ALSO
L<nbdkit(1)>,
L<nbdkit_read_password(3)>,
L<nbdkit-plugin(3)>,
L<nbdkit-filter(3)>.
=head1 AUTHORS
Eric Blake
=head1 COPYRIGHT
Copyright Red Hat
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