nbdkit_stdio_safe - is it safe to interact with stdin and stdout
#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.
NBDKit.stdio_safe : unit -> bool import nbdkit
is_safe = nbdkit.stdio_safe() use nbdkit::*;
pub fn is_stdio_safe() -> boolnbdkit_stdio_safe was added in nbdkit 1.20.
nbdkit(1), nbdkit_read_password(3), nbdkit-plugin(3), nbdkit-filter(3).
Eric Blake
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