RMTOPS(3) | Library Functions Manual | RMTOPS(3) |
rmtops
—
#include <rmt.h>
#include <sys/stat.h>
int
isrmt
(int
fd);
int
rmtaccess
(char
*file, int
mode);
int
rmtclose
(int
fd);
int
rmtcreat
(char
*file, int
mode);
int
rmtdup
(int
fd);
int
rmtfcntl
(int
fd, int cmd,
int arg);
int
rmtfstat
(int
fd, struct stat
*buf);
int
rmtioctl
(int
fd, int request,
char *argp);
int
rmtisatty
(int
fd);
long
rmtlseek
(int
fd, long offset,
int whence);
int
rmtlstat
(char
*file, struct stat
*buf);
int
rmtopen
(char
*file, int flags,
int mode);
int
rmtread
(int
fd, char *buf,
int nbytes);
int
rmtstat
(char
*file, struct stat
*buf);
int
rmtwrite
(int
fd, char *buf,
int nbytes);
rmtops
library provides a simple means of
transparently accessing tape drives on remote machines via
rsh(1) and
rmt(8). 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.
A remote tape drive file name has the form
[user@]hostname:/dev/???
For transparency, the user should include the file
<rmt.h>
, which has the
following defines in it:
#define access rmtaccess #define close rmtclose #define creat rmtcreat #define dup rmtdup #define fcntl rmtfcntl #define fstat rmtfstat #define ioctl rmtioctl #define isatty rmtisatty #define lseek rmtlseek #define lstat rmtlstat #define open rmtopen #define read rmtread #define stat rmtstat #define write rmtwrite
This allows the programmer to use
open(2),
close(2),
read(2),
write(2), etc. in their normal
fashion, with the rmtops
routines taking care of
differentiating between local and remote files. This file should be included
before including the file
<sys/stat.h>, since it redefines the
identifier ``stat'' which is used to declare objects of type
struct stat.
The routines differentiate between local and remote file
descriptors by adding a bias (currently 128) to the file descriptor of the
pipe. The programmer, if he or she must know if a file is remote, should use
isrmt
().
rmtdup
()).
And the appropriate system calls in section 2.
Fred Fish redid them into a general purpose library.
Arnold Robbins added the ability to specify a user name on the remote system, the <rmt.h> include file, this man page, cleaned up the library a little, and made the appropriate changes for 4.3BSD.
Dan Kegel contributed the code to use the rexec(3) library routine.
The rmt(8) 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.
October 16, 2001 | NetBSD 9.2 |