The s6-fdholder-getdump program
s6-fdholder-getdump connects to a
fd-holding daemon listening on a
Unix domain socket, and retrieves its entire state: file descriptors with
their identifiers and expiration dates. It then executes a program with
those file descriptors still open, and the state stored in the
s6-fdholder-getdump [ -t timeout ] path prog...
- s6-fdholder-getdump executes into s6-ipcclient path
It does nothing else: it is just a convenience program.
The s6-ipcclient program connects
to a Unix socket at path, and the
gets the server's state over the socket.
- It executes into prog... with as many more open
file descriptors as there were in the daemon, and information about those
file descriptors in the environment.
- -t timeout : if the operation cannot be
processed in timeout milliseconds, then fail with an error message.
Communications with the server should be near-instant, so this option is
only here to protect users against programming errors (connecting to the
wrong socket, for instance).
s6-fdholder-getdump /service/fdholderd/s s6-fdholder-setdump /service/fdholderd-2/s
will get the state of the s6-fdholderd daemon listening on the /service/fdholderd/s
socket, and transmit it to the other s6-fdholderd daemon listening on the
/service/fdholderd-2/s socket. Note that in this precise case,
program does the same thing more efficiently.
- s6-fdholder-getdump really executes into s6-ipcclient
6 fdclose 7 prog..., so that prog... does not
have a connection with the fd-holding daemon anymore. If you want to
keep the server connection open for prog..., use
s6-ipcclient s6-fdholder-getdumpc manually.
- The exact format of the environment given to prog...
is described in the
- Getting the whole state of a s6-fdholderd daemon requires specific
privileges. Make sure you properly
configure the s6-fdholderd
access rights so your client can perform that operation.