Section 3: library functions
sd_id128_to_string, sd_id128_from_string – Format or parse 128-bit IDs as strings Synopsis #include <systemd/sd-id128.h> char *sd_id128_to_string(sd_id128_t id, char s[33]); int sd_id128_from_string(const char *s, sd_id128_t *ret); Description sd_id128_to_string() formats a 128-bit ID as a character string. It expects the ID and a string array capable of storing 33 characters. The ID will be formatted as 32 lowercase…
sd-id128, sd_id128_t, SD_ID128_MAKE, SD_ID128_CONST_STR, SD_ID128_FORMAT_STR, SD_ID128_FORMAT_VAL, sd_id128_equal – APIs for processing 128-bit IDs Synopsis #include <systemd/sd-id128.h> pkg-config –cflags –libs libsystemd Description sd-id128.h provides APIs to process and generate 128-bit ID values. The 128-bit ID values processed and generated by these APIs are a generalization of OSF UUIDs as defined by m[blue]RFC 4122m[][1] but use a…
sd_get_seats, sd_get_sessions, sd_get_uids, sd_get_machine_names – Determine available seats, sessions, logged in users and virtual machines/containers Synopsis #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 a NULL terminated array of seat identifiers. The returned array and all…
sd_get_seats, sd_get_sessions, sd_get_uids, sd_get_machine_names – Determine available seats, sessions, logged in users and virtual machines/containers Synopsis #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 a NULL terminated array of seat identifiers. The returned array and all…
sd_get_seats, sd_get_sessions, sd_get_uids, sd_get_machine_names – Determine available seats, sessions, logged in users and virtual machines/containers Synopsis #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 a NULL terminated array of seat identifiers. The returned array and all…
sd_get_seats, sd_get_sessions, sd_get_uids, sd_get_machine_names – Determine available seats, sessions, logged in users and virtual machines/containers Synopsis #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 a NULL terminated array of seat identifiers. The returned array and all…
sd_booted – Test whether the system is running the systemd init system Synopsis #include <systemd/sd-daemon.h> int sd_booted(void); Description sd_booted() checks whether the system was booted up using the systemd init system. Return Value On failure, this call returns a negative errno-style error code. If the system was booted up with systemd as init system, this…
sd-readahead – Reference implementation of APIs for controlling boot-time read-ahead Synopsis #include "sd-readahead.h" Description sd-readahead.c and sd-readahead.h provide a reference implementation for APIs for controlling boot-time read-ahead, as implemented by the read-ahead subsystem of the systemd(1) init system. See sd_readahead(3) for more information about the function implemented. Notes This interface is provided by the reference…
sd-login – APIs for tracking logins Synopsis #include <systemd/sd-login.h> pkg-config –cflags –libs libsystemd Description sd-login.h provides APIs to introspect and monitor seat, login session and user status information on the local system. See m[blue]Multi-Seat on Linuxm[][1] for an introduction into multi-seat support on Linux, the background for this set of APIs. Note that these APIs…
sd-journal – APIs for submitting and querying log entries to and from the journal Synopsis #include <systemd/sd-journal.h> pkg-config –cflags –libs libsystemd Description sd-journal.h provides APIs to submit and query log entries. The APIs exposed act both as client for the systemd-journald.service(8) journal service and as parser for the journal files on disk. See sd_journal_print(3), sd_journal_stream_fd(3),…
sd-id128, sd_id128_t, SD_ID128_MAKE, SD_ID128_CONST_STR, SD_ID128_FORMAT_STR, SD_ID128_FORMAT_VAL, sd_id128_equal – APIs for processing 128-bit IDs Synopsis #include <systemd/sd-id128.h> pkg-config –cflags –libs libsystemd Description sd-id128.h provides APIs to process and generate 128-bit ID values. The 128-bit ID values processed and generated by these APIs are a generalization of OSF UUIDs as defined by m[blue]RFC 4122m[][1] but use a…
sd-daemon, SD_EMERG, SD_ALERT, SD_CRIT, SD_ERR, SD_WARNING, SD_NOTICE, SD_INFO, SD_DEBUG – APIs for new-style daemons Synopsis #include <systemd/sd-daemon.h> pkg-config –cflags –libs libsystemd Description sd-daemon.h provide APIs for new-style daemons, as implemented by the systemd(1) init system. See sd_listen_fds(3), sd_notify(3), sd_booted(3), sd_is_fifo(3), sd_watchdog_enabled(3) for more information about the functions implemented. In addition to these functions, a couple…
sctp_sendmsg – Send a message from a SCTP socket. Synopsis #include <netinet/sctp.h> #include <sys/socket.h> #include <sys/types.h> int sctp_sendmsg(int sd, const void *msg, size_t len, struct sockaddr *to, socklen_t tolen, uint32_t ppid, uint32_t flags, uint16_t stream_no, uint32_t timetolive, uint32_t context); Description sctp_sendmsg is a wrapper library function that can be used to send a message from…
sctp_send – Send a message from a SCTP socket. Synopsis #include <netinet/sctp.h> #include <sys/socket.h> #include <sys/types.h> int sctp_send(int sd, const void *msg, size_t len, const struct sctp_sndrcvinfo *sinfo, uint32_t flags); Description sctp_send is a wrapper library function that can be used to send a message from a socket without the use of the CMSG header…
sctp_recvmsg – Receive a message from a SCTP socket. Synopsis #include <netinet/sctp.h> #include <sys/socket.h> #include <sys/types.h> int sctp_recvmsg(int sd, void *msg, size_t len, struct sockaddr *from, socklen_t *fromlen, struct sctp_sndrcvinfo *sinfo, int *msg_flags); Description sctp_recvmsg is a wrapper library function that can be used to receive a message from a socket while using the advanced…
sctp_peeloff – Branch off an association into a separate socket. Synopsis #include <netinet/sctp.h> #include <sys/socket.h> #include <sys/types.h> int sctp_peeloff(int sd, sctp_assoc_t assoc_id); Description sctp_peeloff branches off an existing association assoc_id on a one-to-many style socket sd into a separate socket. The new socket is a one-to-one style socket. This is particularly desirable when, for instance,…
sctp_optinfo – Get options on a SCTP socket. Synopsis #include <netinet/sctp.h> #include <sys/socket.h> #include <sys/types.h> int sctp_opt_info(int sd, sctp_assoc_t id, int opt, void *arg, socklen_t *size); Description sctp_opt_info is a wrapper library function that can be used to get SCTP level options on a socket. sd is the socket descriptor for which the option is…
sctp_getpaddrs – Returns all peer addresses in an association. Synopsis #include <netinet/sctp.h> #include <sys/socket.h> #include <sys/types.h> int sctp_getpaddrs(int sd, sctp_assoc_t assoc_id, struct sockaddr **addrs); void sctp_freepaddrs(struct sockaddr *addrs); Description sctp_getpaddrs returns all peer addresses in an association. On return, addrs will point to a dynamically allocated packed array of sockaddr structures of the appropriate type…
sctp_getladdrs – Returns all locally bound addresses on a socket. Synopsis #include <netinet/sctp.h> #include <sys/socket.h> #include <sys/types.h> int sctp_getladdrs(int sd, sctp_assoc_t assoc_id, struct sockaddr **addrs); void sctp_freeladdrs(struct sockaddr *addrs); Description sctp_getladdrs returns all locally bound addresses on a socket. On return, addrs will point to a dynamically allocated packed array of sockaddr structures of the…
sctp_connectx – initiate a connection on an SCTP socket using multiple destination addresses. Synopsis #include <netinet/sctp.h> #include <sys/socket.h> #include <sys/types.h> int sctp_connectx(int sd, struct sockaddr *addrs, int addrcnt, sctp_assoc_t *id); Description sctp_connectx initiates a connection to a set of addresses passed in the array addrs to/from the socket sd. addrcnt is the number of addresses…