gnuserv(1)
gnuserv, gnuclient, gnudoit - Server and Clients for GNU Emacs
As shipped in IRIX 6.5.5. Unchanged since IRIX 6.5.
NAME gnuserv, gnuclient, gnudoit - Server and Clients for GNU Emacs SYNOPSIS gnuclient [-q] [[-h hostname] [-p port] [-r pathname]] [[+line] path] ... gnudoit [-q] [[-h hostname] [-p port]] [sexpr] ... gnuserv DESCRIPTION gnuclient allows the user to request a running GNU Emacs process to edit the named files or directories. gnudoit allows the user to request a running GNU Emacs process to evaluate the given arguments inside a progn LISP form. gnuserv is the server program that is set running by GNU Emacs to handle all incoming and outgoing requests. It is not usually invoked directly, but is started from GNU Emacs by the LISP form (server-start). OPTIONS -q This option informs both gnuclient and gnudoit to exit once connection has been made with the GNU Emacs process. Normally gnuclient waits until all of the files on the command line have been finished with (their buffers killed) by the GNU Emacs process, and gnudoit normally waits around for evaluation of its arguments by the GNU Emacs process, and prints the results or error conditions. -h hostname Used only with Internet-domain sockets, this option specifies the host machine which should be running gnuserv. If this option is not specified then the value of the environment variable GNU_HOST is used if set, otherwise the hostname of the machine running the program is used. Note that an internet address may be specified instead of a hostname which can speed up connections to the server by quite a bit, especially if the client machine is running YP. Note also that a hostname of unix can be used to specify that the connection to the server should use a Unix-domain socket (if supported) rather than an Internet-domain socket. -p port Used only with Internet-domain sockets, this option specifies the service port used to communicate between server and clients. If this option is not specified, then the value of the environment variable GNU_PORT is used, if set, otherwise a service called ``gnuserv'' is looked up in the services database. Finally, if no other value can be found for the port, then a default port is used which is usually 21490 + uid. Note that since gnuserv doesn't allow command-line options, the port for it will have to be specified via one of the alternative methods. -r pathname Used only with Internet-domain sockets, the pathname argument may be needed to inform GNU Emacs how to reach the root directory of a remote machine. gnuclient prepends this string to each path argument given. For example, if you were trying to edit a file on a client machine called otter, whose root directory was accessible from the server machine via the path /net/otter, then this argument should be set to '/net/otter'. If this option is omitted, then the value is taken from the environment variable GNU_NODE, if set, or the empty string otherwise. Note that on hp9000/s300 and hp9000/s800, the pathname, if not specified by the user, is guessed. path This is the path of the file to be edited. If the file is a directory, then the directory browsers dired or monkey are usually invoked instead. sexpr This is part of a GNU Emacs LISP expression to evaluate. All the sexprs are concatenated together and wrapped in a progn form before sending to GNU Emacs. SETUP In order to use the programs, the file gnuserv.el can be copied into a directory on your GNU Emacs load-path, and loaded into GNU Emacs by the GNU Emacs LISP form (load "gnuserv"). The server can then be started by the GNU Emacs LISP form (server-start). EXAMPLE gnudoit -q '(mh-smail)' gnuclient -h otter -r /net/otter /tmp/* SYSV IPC SysV IPC is used to communicate between gnuclient, gnudoit and gnuserv if the symbol SYSV_IPC is defined at the top of gnuserv.h. This is incompatible with both Unix-domain and Internet-domain socket communication as described below. A file called /tmp/gsrv??? is created as a key for the message queue, and if removed will cause the communication between server and client to fail until the server is restarted. UNIX-DOMAIN SOCKETS A Unix-domain socket is used to communicate between gnuclient, gnudoit and gnuserv if the symbol UNIX_DOMAIN_SOCKETS is defined at the top of gnuserv.h. A file called /tmp/gsrv??? is created for communication and if deleted will cause communication between server and client to fail. INTERNET-DOMAIN SOCKETS Internet-domain sockets are used to communicate between gnuclient, gnudoit and gnuserv if the symbol INTERNET_DOMAIN_SOCKETS is defined at the top of gnuserv.h. Both Internet-domain and Unix-domain sockets can be used at the same time. SECURITY Using Internet-domain sockets, a more robust form of security is needed that wasn't necessary with either Unix-domain sockets or SysV IPC. gnuserv performs a limited form of security at the machine level. By default only connections from the host where the server is running will be allowed. All other server connections will be rejected with a cryptic message (which is displayed only by gnudoit). Alternatively, if the variable GNU_SECURE can be found in gnuserv's environment, and it names a readable filename, then this file is opened and assumed to be a list of hosts, one per line, from which the server will allow requests. Note that a host may be either a internet address, or a hostname. If this file contains a lot of hostnames then the server may take quite a time to start up. KNOWN BUGS If GNU Emacs attempts to send a string containing a newline character to gnuserv, then gnuserv will die. FILES /tmp/gsrv??? ~/.emacs GNU Emacs customization file, see emacs(1). AUTHOR. Andy Norman (ange@hplb.hpl.hp.com), based heavily upon etc/emacsclient.c, etc/server.c and lisp/server.el from the GNU Emacs 18.52 distribution.