1 03/21/85 x
 2 
 3 Syntax as a command:  x function {args}
 4 
 5 
 6 Function:  allows drivers to execute an admin exec_com on a
 7 site-defined basis.
 8 
 9 
10 Arguments:
11 function
12    is a site-defined function name.
13 
14 
15 Control arguments:
16    are any arguments needed to implement function.
17 
18 
19 Notes:  When the user issues the x command, the driver constructs the
20 command line:
21 
22       exec_com >ddd>idd>NAME function {args}
23 
24 where function and args are as above; NAME is either
25 <major_device>_admin.ec for standard drivers or <station_id>_admin.ec
26 for remote drivers.  If NAME is not found, the driver will look for the
27 default of iod_admin.ec.  Added names can be used to group exec_coms
28 into categories.
29 
30 
31 An I/O daemon admin exec_com is written by a site administrator to
32 provide site-defined driver x command functions.  The use of admin
33 exec_coms is optional, but when missing, the driver x command will not
34 work.  See the Multics System Maintenance Procedures manual, Order No.
35 AM81, for the application of the admin exec_com to the creation of a
36 driver-to-driver message facility.
37 
38 
39 Each I/O daemon admin exec_com is located in the >ddd>idd directory and
40 follows standard exec_com rules.  There are two types of admin
41 exec_coms:  general and device specific.  These differ only in segment
42 name, to allow the site to separate x command functions by device name
43 (station_id for remote stations).  The iod_admin.ec segment is the
44 general exec_com and will be used by any driver that cannot find a
45 device-specific exec_com.  A <device>_admin.ec segment is a
46 device-specific exec_com for the given major device; for example,
47 prta_admin.ec is specific to device prta.  Added names can be used to
48 group several devices under a single device-specific exec_com.
49 
50 
51 The Multics command iod_command may be used within an admin exec_com to
52 execute arbitrary I/O daemon commands.  For example:
53 
54       iod_command defer_time 30
55 
56 may be used in an admin exec_com to change the auto defer time limit
57 for the current driver to 30 minutes.
58 
59 When writing an I/O daemon admin exec_com, the administrator must
60 remember that the process that executes it will, most likely, have full
61 SysDaemon access and privileges to the system.  Therefore, care must be
62 given in choosing what functions should be placed at the hands of a
63 remote station operator or an inexperienced device operator.
64 
65 
66 The Multics command iod_command may be used within an admin exec_com to
67 execute arbitrary I/O daemon commands.  For example:
68 
69       iod_command defer_time 30
70 
71 may be used in an admin exec_com to change the auto defer time limit
72 for the current driver to 30 minutes.