Provided by: systemd_251.4-1ubuntu7_amd64 bug


       systemd-socket-activate - Test socket activation of daemons


       systemd-socket-activate [OPTIONS...] daemon [OPTIONS...]


       systemd-socket-activate may be used to launch a socket-activated service program from the
       command line for testing purposes. It may also be used to launch individual instances of
       the service program per connection.

       The daemon to launch and its options should be specified after options intended for

       If the --inetd option is given, the socket file descriptor will be used as the standard
       input and output of the launched process. Otherwise, standard input and output will be
       inherited, and sockets will be passed through file descriptors 3 and higher. Sockets
       passed through $LISTEN_FDS to systemd-socket-activate will be passed through to the
       daemon, in the original positions. Other sockets specified with --listen= will use
       consecutive descriptors. By default, systemd-socket-activate listens on a stream socket,
       use --datagram and --seqpacket to listen on datagram or sequential packet sockets instead
       (see below).


       -l address, --listen=address
           Listen on this address. Takes a string like "2000" or "".

       -a, --accept
           Launch an instance of the service program for each connection and pass the connection

       -d, --datagram
           Listen on a datagram socket (SOCK_DGRAM), instead of a stream socket (SOCK_STREAM).
           May not be combined with --seqpacket.

           Listen on a sequential packet socket (SOCK_SEQPACKET), instead of a stream socket
           (SOCK_STREAM). May not be combined with --datagram.

           Use the inetd protocol for passing file descriptors, i.e. as standard input and
           standard output, instead of the new-style protocol for passing file descriptors using
           $LISTEN_FDS (see above).

       -E VAR[=VALUE], --setenv=VAR[=VALUE]
           Add this variable to the environment of the launched process. If VAR is followed by
           "=", assume that it is a variable–value pair. Otherwise, obtain the value from the
           environment of systemd-socket-activate itself.

           Specify names for the file descriptors passed. This is equivalent to setting
           FileDescriptorName= in socket unit files, and enables use of
           sd_listen_fds_with_names(3). Multiple entries may be specifies using separate options
           or by separating names with colons (":") in one option. In case more names are given
           than descriptors, superfluous ones will be ignored. In case less names are given than
           descriptors, the remaining file descriptors will be unnamed.

       -h, --help
           Print a short help text and exit.

           Print a short version string and exit.


           See sd_listen_fds(3).

           Same as in systemd(1).


       Example 1. Run an echo server on port 2000

           $ systemd-socket-activate -l 2000 --inetd -a cat

       Example 2. Run a socket-activated instance of systemd-journal-gatewayd(8)

           $ systemd-socket-activate -l 19531 /lib/systemd/systemd-journal-gatewayd


       systemd(1), systemd.socket(5), systemd.service(5), systemd-run(1), sd_listen_fds(3),
       sd_listen_fds_with_names(3), cat(1)