Home
Main website
Display Sidebar
Hide Ads
Recent Changes
View Source:
rmt(8)
Edit
PageHistory
Diff
Info
LikePages
---- __NAME__ rmt - remote magtape protocol module __SYNOPSIS__ rmt __DESCRIPTION__ Rmt is a program used by tar, cpio, mt, and the remote dump and restore programs in manipulating a magnetic tape drive through an interprocess communication connection. Rmt is normally started up with an rexec(3) or rcmd(3) call or the rsh(1) command. The rmt program accepts requests specific to the manipula- tion of magnetic tapes, performs the commands, then responds with a status indication. All responses are in ASCII and in one of two forms. Successful commands have responses of: __A__numbern Number is an ASCII representation of a decimal number. Unsuccessful commands are responded to with: __ E__error-numbernerror-message n Error-number is one of the possible error numbers described in intro(2) and error-message is the corresponding error string as printed from a call to perror(3). The protocol is comprised of the following commands, which are sent as indi- cated - no spaces are supplied between the command and its arguments, or between its arguments, and n indicates that a newline should be supplied: __ O__devicenmoden Open the specified deviceusing the indicatedmode.Deviceis a full pathname and modeis anASCIIrepresentation of a decimal number suitable forpassing to open(2).If a device had already been opened, it is closed before a new open is performed. __C__devicen Close the currently open device. The devicespecified is ignored. __L__offsetn whencen Perform an lseek(2) operation using the specified parameters. The response value is that returned from the lseek call. __W__countn Write data onto the open device. Rmt reads count bytes from the connection, aborting if a premature end-of-file is encountered. The response value is that returned from the write(2) call. __R__countn Read count bytes of data from the open device. If count exceeds the size of the data buffer (10 kilo- bytes), it is truncated to the data buffer size. rmt then performs the requested read(2) and responds with __A__count-readn if the read was successful; otherwise an error in the standard format is returned. If the read was successful, the data read is then sent. __I__operationncountn Perform a MTIOCOP ioctl(2) command using the speci- fied parameters. The parameters are interpreted as the ASCII representations of the decimal values to place in the mt_op and mt_count fields of the struc- ture used in the ioctl call. The return value is the count parameter when the operation is successful. __S__ Return the status of the open device, as obtained with a MTIOCGET ioctl call. If the operation was successful, an ``ack'' is sent with the size of the status buffer, then the status buffer is sent (in binary). Any other command causes rmt to exit. __DIAGNOSTICS__ All responses are of the form described above. __SEE ALSO__ tar(1), cpio(1), mt(1), rsh(1), rcmd(3), rexec(3), mtio(4), rdump(8), rrestore(8) __BUGS__ People should be discouraged from using this for a remote file access protocol. __HISTORY__ The rmt command appeared in 4.2 BSD . 4.2 Berkeley !DistributionDecember 11, 1993 1 ----
One page links to
rmt(8)
:
Man8r
This page is a man page (or other imported legacy content). We are unable to automatically determine the license status of this page.