# systemd-socket-activate

## NAME



           systemd-socket-activate - Test socket activation of daemons
    


## SYNOPSIS



    
           **systemd-socket-activate**[OPTIONS...] _COMMAND_ [ARGS...]
    


## DESCRIPTION



           **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



           **-l** _address_ , **--listen=**_address_
               Listen on this _address_. Takes a string like "2000" or
               "127.0.0.1:2001".
    
               Added in version 230.
    
           **-a** , **--accept**
               Launch an instance of the service program for each connection
               and pass the connection socket. May not be combined with
               **--now**.
    
               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.
    
           **--seqpacket**
               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.
    
           **--inetd**
               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).
    
               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.
    
           **--fdname=**_NAME_**[:**_NAME_...]
               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.
    
           **--now**
               Start the service program instantly, instead of waiting for a
               connection on the socket(s). May not be combined with
               **--accept**.
    
               Added in version 258.
    
           **-h** , **--help**
               Print a short help text and exit.
    
           **--version**
               Print a short version string and exit.
    


## ENVIRONMENT VARIABLES



           _$LISTEN_FDS_ , _$LISTEN_PID_ , _$LISTEN_FDNAMES_
               See sd_listen_fds(3).
    
               Added in version 230.
    
           _$SYSTEMD_LOG_TARGET_ , _$SYSTEMD_LOG_LEVEL_ , _$SYSTEMD_LOG_TIME_ ,
           _$SYSTEMD_LOG_COLOR_ , _$SYSTEMD_LOG_LOCATION_
               Same as in systemd(1).
    
               Added in version 230.
    


## EXAMPLES



           **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 /usr/lib/systemd/systemd-journal-gatewayd
    


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