The Remote File System was a distributed file system

Distributed file system

Network file system may refer to:* A distributed file system, which is accessed over a computer network* Network File System , a specific brand of distributed file system...

 developed by AT&T

AT&T

AT&T Inc. is an American multinational telecommunications corporation headquartered in Whitacre Tower, Dallas, Texas, United States. It is the largest provider of mobile telephony and fixed telephony in the United States, and is also a provider of broadband and subscription television services...

 in the 1980s. It was first delivered with UNIX System V

UNIX System V

Unix System V, commonly abbreviated SysV , is one of the first commercial versions of the Unix operating system. It was originally developed by American Telephone & Telegraph and first released in 1983. Four major versions of System V were released, termed Releases 1, 2, 3 and 4...

 Release 3 (SVR3).

Compared to NFS it made quite different design decisions. Instead of focusing on reliable operation in the presence of failures, it focused on preserving UNIX file system semantics across the network.
Unlike NFS (before version 4), the RFS server

Server (computing)

In the context of client-server architecture, a server is a computer program running to serve the requests of other programs, the "clients". Thus, the "server" performs some computational task on behalf of "clients"...

 maintains state to keep track of how many times a file has been opened, if any process has locked

Lock (computer science)

In computer science, a lock is a synchronization mechanism for enforcing limits on access to a resource in an environment where there are many threads of execution. Locks are one way of enforcing concurrency control policies.-Types:...

 the file, etc. RFS was a product from Bell Laboratories.
People involved in the creation of RFS: Andrew P. Rifkin, Michael P. Forbes, Richard L. Hamilton, Michael Sabrio, Suryakanta Shah, and Kang Yueh.

Features

• Provides complete UNIX/POSIX file semantics. (File locking, etc.)
• Allows mounting of devices across the network (e.g. /dev/cdrom can be accessed remotely)
• Transparent access to files. Users needn't know where a file is located.

Remote system call interface

• ACCESS
• SYSACCT
• CHDIR Change directory
• CHMOD Change file mode
• CHOWN Change file owner
• CHROOT
• CLOSE Close a file
• CREAT Create a file
• EXEC Execute a file
• EXECE Execute a file with an environment
• FCNTL
• FSTAT Stat a file using a file descriptor
  File descriptor
  In computer programming, a file descriptor is an abstract indicator for accessing a file. The term is generally used in POSIX operating systems...
  
  
• FSTATFS Stat a file system using a file descriptor
• IOCTL
• LINK First half of link operation
• LINK1 Second half of link operation
• MKNOD Make block or character special file
• OPEN Open a file
• READ Read from a file
• SEEK Seek on a file
• STAT Stat a file using pathname
• STATFS Stat a file system using pathname
• UNLINK
• UTIME
• UTSSYS Return information about a mounted files
• WRITE
• GETDENTS Read directory entries in a file system
• MKDIR
• RMDIR
• SRMOUNT Server side of remote mount
• SRUMOUNT Server side of remote unmount
• COREDUMP Dump core request
• WRITEI Internal form of write system call
• READI Internal form of read system call
• RSIGNAL Sendremote signal
• SYNCTIME Synchronize time between machines
• IPUT Free a remote inode
• IUPDATE Update a remote inode
• UPDATE Write modified buffers back to disk.

See also

• AppleTalk
  AppleTalk
  AppleTalk is a proprietary suite of protocols developed by Apple Inc. for networking computers. It was included in the original Macintosh released in 1984, but is now unsupported as of the release of Mac OS X v10.6 in 2009 in favor of TCP/IP networking...
  
  
• Network File System
• Samba
• Server Message Block
  Server Message Block
  In computer networking, Server Message Block , also known as Common Internet File System operates as an application-layer network protocol mainly used to provide shared access to files, printers, serial ports, and miscellaneous communications between nodes on a network. It also provides an...
  
  
• WebDAV
  WebDAV
  Web-based Distributed Authoring and Versioning is a set of methods based on the Hypertext Transfer Protocol that facilitates collaboration between users in editing and managing documents and files stored on World Wide Web servers...