ramfs(4) [plan9 man page]

RAMFS(4)						     Kernel Interfaces Manual							  RAMFS(4)

NAME

       ramfs  - memory file system

SYNOPSIS

       ramfs [ -i ] [ -s ] -m [ mountpoint ]

DESCRIPTION

       Ramfs  starts  a process that mounts itself (see bind(2)) on mountpoint (default /tmp).	The ramfs process implements a file tree rooted at
       dir, keeping all files in memory.  Initially the file tree is empty.

       The -i flag tells ramfs to use file descriptors 0 and 1 for its communication channel rather than create a pipe.  This makes it possible to
       use  ramfs as a file server on a remote machine: the file descriptors 0 and 1 will be the network channel from ramfs to the client machine.
       The -s flag causes ramfs to post its channel on /srv/ramfs rather than mounting it on mountpoint, enabling multiple clients to  access  its
       files.  However, it does not authenticate its clients and its implementation of groups is simplistic, so it should not be used for precious
       data.

       This program is useful mainly as an example of how to write a user-level file server.  It can also be used to provide high-performance tem-
       porary files.

SOURCE

       /sys/src/cmd/ramfs.c

SEE ALSO

       bind(2)

																	  RAMFS(4)

SRV(3)							     Library Functions Manual							    SRV(3)

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 pro-
       cesses 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 reg-
       istered.

       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", 1, 0666);
	      sprint(buf, "%d", p[0]);
	      write(fd, buf, strlen(buf));
	      close(fd);
	      close(p[0]);
	      write(p[1], "hello", 5);

       At  this  point, any process may open and read /srv/namedpipe to receive the hello string.  Data written to /srv/namedpipe will be received
       by executing

	      read(p[1], buf, sizeof buf);

       in the above process.

SOURCE

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

																	    SRV(3)