nbdkit_stdio_safe - Man Page

 #include <nbdkit-plugin.h>

 int nbdkit_stdio_safe (void);

The 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 -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 .config_complete.  Once nbdkit reaches .get_ready, the plugin should assume that nbdkit may have closed the original stdin and stdout in order to become a daemon.

nbdkit-sh-plugin(3) uses this function to determine whether it is safe to support script=- to read a script from stdin.  Also constructs like password=- (see nbdkit_read_password(3)) are disabled when reading from stdio is not safe.

The function returns 1 (safe) or 0 (not safe).

It cannot return an error.

In nbdkit-ocaml-plugin(3):

 NBDKit.stdio_safe : unit -> bool

In nbdkit-python-plugin(3):

 import nbdkit
 is_safe = nbdkit.stdio_safe()

In nbdkit-rust-plugin(3):

 use nbdkit::*;
 pub fn is_stdio_safe() -> bool

nbdkit_stdio_safe was added in nbdkit 1.20.

nbdkit(1), nbdkit_read_password(3), nbdkit-plugin(3), nbdkit-filter(3).

Eric Blake

Copyright Red Hat

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nbdkit-plugin(3), nbdkit_read_password(3).