NIO CommKit Host Interface Installation and System Administration Manual

DKDO(1C) DKDO(1C)
E-12 CommKit Host Interface, Release 4.0
NAME
dkdo – transparent remote execution facility
SYNOPSIS
dkdo [ –f controltable ] command [ args ... ]
command [ args... ]
DESCRIPTION
dkdo provides a generalized, transparent remote execution facility with automatic file transfer. One use of
dkdo is to emulate a command such as lp(1) requiring facilities like line printers or RJE support not present
on the local machine. It works by placing a call through the AT&T data switch network to a host that does
have the required facilities, sending any input file arguments to the remote system, executing the command
there, then bringing back any output files.
The input files are placed in a new directory created under /tmp on the remote machine which is used as the
current directory when the command is invoked. Any files created in that directory by the command are
brought back to the current directory on the local machine upon completion. The remote command is
executed with the same standard input, output, and error file descriptors as on the local machine.
The function of the command is controlled by a controltable which describes how the commands are to be
executed and the format of the arguments. If not specified by the -f argument, the default file /etc/opt/dk/
dkdotab is used. The format of the controltable is described in the manual page for dkdotab(4).
Invoking the program by the name dkdo is the explicit invocation format. Usually, however, the second,
implicit format is used by linking the dkdo program to lp(1) or another program. Then users may use the
emulated command as if it were actually located on the local machine. In this case the link name (that is, lp(1)
is the command that will be remotely executed.
Multiple Interfaces
If multiple interface boards are installed on the originating host, then dkdo will use the default processing to
select the interface for the outgoing call. See dkdial(3X) and authorize(1M) for more information.
FILES
/opt/dk/bin directory in which this command resides
/etc/opt/dk/dkhosts host control file for destination mapping
/etc/opt/dk/dkdotab default dkdo control table
SEE ALSO
authorize(1M), dkdotab(4), srvtab(4)
lp(1) in the UNIX System V User’s Reference Manual
DIAGNOSTICS
The dkdo command will fail on the remote machine if there is no space left in the file system containing
/tmp. One of the following error messages will appear on the user’s terminal on the local machine:
mkdir: Failed to make directory "dkdo.xyz";
No space left on device
dkpp: cannot link filename
dkpp: filename extract write error
where filename is the full pathname of the file to be transferred to/from the remote/local host computer. Lack
of space on the remote is not the only case where these error messages may appear.