sd_get_seats

systemd

sd_get_seats

sd_get_sessions

sd_get_uids

sd_get_machine_names

Determine available seats, sessions, logged in users and virtual machines/containers

#include <systemd/sd-login.h>

int

sd_get_seats

char ***

seats

int

sd_get_sessions

char ***

sessions

int

sd_get_uids

uid_t **

users

int

sd_get_machine_names

char ***

machines

Description

sd_get_seats() may be used to determine all currently available local seats. Returns the number of seat identifiers and if the input pointer is non-NULL, a NULL-terminated array of seat identifiers is stored at the address. The returned array and all strings it references need to be freed with the libc free(3) call after use. Note that instead of an empty array NULL may be returned and should be considered equivalent to an empty array.

Similarly, sd_get_sessions() may be used to determine all current login sessions.

Similarly, sd_get_uids() may be used to determine all Unix users who currently have login sessions.

Similarly, sd_get_machine_names() may be used to determine all current virtual machines and containers on the system.

Note that the returned lists are not sorted and in an undefined order.

Return Value

On success, sd_get_seats(), sd_get_sessions(), sd_get_uids() and sd_get_machine_names() return the number of entries in the arrays. On failure, these calls return a negative errno-style error code.

Errors

Returned errors may indicate the following problems:

-ENOMEM
Memory allocation failed.

History

sd_get_machine_names() was added in version 203.