systemd-socket-activate(1) — Linux manual page


SYSTEMD-...-ACTIVATE(1)  systemd-socket-activate SYSTEMD-...-ACTIVATE(1)

NAME         top

       systemd-socket-activate - Test socket activation of daemons

SYNOPSIS         top

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

DESCRIPTION         top

       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 systemd-socket-activate.

       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).

OPTIONS         top

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

           Added in version 230.

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

           Added in version 230.

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

           Added in version 230.

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

           Added in version 230.

           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

           Added in version 230.

       -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.

           Added in version 230.

           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.

           Added in version 230.

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

           Print a short version string and exit.


           See sd_listen_fds(3).

           Added in version 230.

           Same as in systemd(1).

           Added in version 230.

EXAMPLES         top

       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-

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

SEE ALSO         top

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

COLOPHON         top

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       This page was obtained from the project's upstream Git repository
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systemd 255                                      SYSTEMD-...-ACTIVATE(1)

Pages that refer to this page: systemd.directives(7)systemd.index(7)