NAME

	srv – server registry

SYNOPSIS

	bind #s /srv #s/service1 #s/service2 ...

DESCRIPTION

The srv device provides a one–level directory holding already–open channels to services. In effect, srv is a bulletin board on which processes may post open file descriptors to make them available to other processes. To install a channel, create a new file such as /srv/myserv and then write a text string (suitable for strtoul; see atof(2)) giving the file descriptor number of an open file. Any process may then open /srv/myserv to acquire another reference to the open file that was registered. An entry in srv holds a reference to the associated file even if no process has the file open. Removing the file from /srv releases that reference. It is an error to write more than one number into a server file, or to create a file with a name that is already being used.

EXAMPLE

To drop one end of a pipe into /srv, that is, to create a named pipe: int fd, p[2]; char buf[32]; pipe(p); fd = create("/srv/namedpipe", OWRITE, 0666); fprint(fd, "%d", p[0]); close(fd); close(p[0]); fprint(p[1], "hello"); At this point, any process may open and read /srv/namedpipe to receive the hello string. Data written to /srv/namedpipe can be received by executing read(p[1], buf, sizeof buf); in the above process.

SOURCE

	/sys/src/9/port/devsrv.c

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