Sierra Video Viper Component Series, User Manual

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SIERRA VIDEO
78
Basic “G” Command:
Action From Syntax
Modify Host G command_name {
arguments… } ~
Query
Host G command_name {
arguments… } ~
Query Response
Router G command_name { arguments… } ~
Modify is Protected:
Yes
Report Changes: No
The command "
G
" is used to query or modify a router configuration parameter or
parameters.
Summary lines at the start of each command section describe, for each type of command
action (Modify, Query, or Query Response), whether the command is sent to the router or
from the router and what the
syntax
of the command is. They also indicate whether or not
the
modify
form of the command is password-protected or not (“Modify is Protected”) and
whether or not the command participates in automatic reporting of parameter changes
(“Report Changes”) as described under the “G REPORT_CHANGES” command.
Each command has three possible syntax forms:
1.
Modify: this form is sent to the router to modify a parameter value
2.
Query:
this form is sent to the router to query for a parameter value
3.
Query Response:
this form is sent
by the router
to report the value of a parameter in
response to receiving a Query or in response to a change in the parameter value when
automatic reporting of parameter changes is turned on.
Generally, the command arguments identify the parameter that is being queried or
modified, and provide its new value if it is being modified. The first argument following the
“G” command character is a
command name.
Additional arguments may be required for
some command names to completely specify the parameter in question. After those, one
or more additional
optional
arguments may give a new value for the parameter. All
arguments are separated from one another by commas.
When the
Modify
form of the command is used and if the new value is a valid value, the
router will change the parameter value to this new value, providing that “Modify is
Protected” says “No” or the administrator password has been sent using the “K”
command. It will then report the new value to all router control ports that have requested
these reports, providing that “Report Changes” says “Yes”. If a new value is provided that
is an illegal value, the parameter is left unchanged and no “G” command is sent.
When the
Query
form of the command is used, the
Query Response
form of the
command is returned to the control port that sent the
Query
command, reporting the
current value of the parameter. The
Query
form of a command is normally the same as
the
Modify
form except that the new parameter values are not included. The
Query
Response
form of a command is normally the same as the
Modify
form (but of course the
sender and receiver are reversed in these two cases).
Some “G” commands may initiate an action or report the occurrence of an event, instead
of querying or changing a router parameter.
Commas
are used to separate arguments in the “G” command.
Space characters
should not appear within the “G” command arguments, except when
they appear within strings. Also, a single space character is allowed after the “G”