*nix Documentation Project
·  Home
 +   man pages
·  Linux HOWTOs
·  FreeBSD Tips
·  *niX Forums

  man pages->IRIX man pages -> rmtops (3)              


RMTOPS(3)							     RMTOPS(3)

NAME    [Toc]    [Back]

     rmtops - remote tape drive	access routines

SYNOPSIS    [Toc]    [Back]

     int rmtaccess(char	*path, int amode);
     int rmtclose(int fildes);
     int rmtcreat(char *path, int mode);
     int rmtfstat(int fildes, struct stat *buf);
     int rmtioctl(int fildes, int request, int arg);
     int rmtopen(char *path, int oflag,	int mode);
     int rmtread(int fildes, char *buf,	unsigned int nbyte);
     int rmtwrite(int fildes, char *buf, unsigned int nbyte);

DESCRIPTION    [Toc]    [Back]

     Rmtops provides a simple means of transparently accessing tape drives on
     remote machines over a network, via rsh(1)	and rmt(1M).  This version of
     the library expects the remote rmt	program	to be version 2, which is
     fairly widespread.	 These routines	are used like their corresponding
     system calls, but allow the user to open up a tape	drive on a remote
     system on which he	or she has an account and the appropriate remote
     permissions.  rmtaccess() always returns 0	in the remote case, since the
     protocol doesn't support this concept, deferring access errors until the
     rmtopen or	rmtcreat.

     A remote tape drive file name has the form


     where system is the remote	system,	/dev/??? is the	particular drive on
     the remote	system (raw, blocked, rewinding, non-rewinding,	etc.), and the
     optional user is the login	name to	be used	on the remote system, if
     different from the	current	user's login name.  This corresponds to	the
     remote syntax used	by rcp(1).  Note that the remote device	must in	fact
     be	a device, and must reside below	/dev on	the remote system.

     The routines differentiate	between	local and remote file descriptors by
     adding a bias to the file descriptor of the pipe.	The programmer,	if he
     must know if a file is remote, should use the isrmt function.  Up to 4
     remote devices may	be in simultaneous use by one program at the same

FILES    [Toc]    [Back]

	  Contains the remote tape library.  To	include	the library with a
	  program, add the flag	-lrmt to the cc(1) command line.

SEE ALSO    [Toc]    [Back]

     rcp(1), rsh(1), rmt(2), and the appropriate system	calls in section 2.

									Page 1

RMTOPS(3)							     RMTOPS(3)

     Several of	these routines will return -1 and set errno to EOPNOTSUPP, if
     they are given a remote file name or a file descriptor on an open remote
     file (e.g., rmtdup).

BUGS    [Toc]    [Back]

     See diagnostics above.  It	is to be hoped that true remote	file systems
     will eventually appear, and eliminate the need for	these routines.

     There is no way to	use remote tape	drives with the	stdio(3) package with
     the current implementation.

     The rmt(1m) protocol is not very capable.	In particular, it relies on
     TCP/IP sockets for	error free transmission, and does no data validation
     of	its own.

     The rmt program allows no more than 10K bytes to be transferred at	one
     time.  The	rmtread	and rmtwrite routines will transfer data in multiple
     chunks if necessary to meet this requirement, and the rmt program on the
     remote will reassemble the	data and pass it via the read and write	system
     calls as a	single system call.

ORIGINAL AUTHORS    [Toc]    [Back]

     This set of routines is passed on a package posted	to the Usenet group
     comp.sources.unix,	circa 1989.  Further changes, particularly to the
     rmtioctl code, were made at Silicon Graphics.
     Jeff Lee (gatech!jeff) wrote the original routines	for accessing tape
     drives via	rmt(1m).

     Fred Fish (unisoft!fnf) redid them	into a general purpose library.

     Arnold Robbins (gatech!arnold) added the ability to specify a user	name
     on	the remote system, this	man page, and cleaned up the library a little.

									PPPPaaaaggggeeee 2222
[ Back ]
 Similar pages
Name OS Title
rmtops NetBSD access tape drives on remote machines
rmt Tru64 Allows remote access to magnetic tape devices
mt-gnu Linux control magnetic tape drive operation
rmt HP-UX remote magnetic-tape protocol module
scsi_tape HP-UX SCSI sequential access (tape) device driver
tapeio IRIX FORTRAN tape device specific I/O routines
mknetpr IRIX provide access to a remote printer
disableXhost IRIX utility for disabling remote access to local display
mkbsdnetpr IRIX provide access to a remote printer using the BSD printing protocols
remote.unknown Tru64 Logs access attempts by unknown remote systems
Copyright © 2004-2005 DeniX Solutions SRL
newsletter delivery service