NET/MASTER Network Control Language (NCL) Reference Manual

CNMREAD
Verbs
106126 Tandem Computers Incorporated 3–29
CNMSENDs have been issued (that is, further requests have queued response
information). When all RUs have been processed for a particular request (or where the
CNMSEND request did not solicit) and the response has already been processed by a
CNMREAD TYPE=RESP, a subsequent CNMREAD TYPE=RESP returns the response
information from the next CNMSEND verb.
When a single CNMSEND request that does not solicit data is followed by a
CNMREAD request for data, the CNMREAD completes with the &SYS.RETCODE
system variable set to 4. However, if any subsequent CNMSEND verb that did solicit
data was issued before the CNMREAD verb, the CNMREAD would be satisfied by
data from the first such request. In either case, the response information to those
intervening requests that did not satisfy a CNMREAD is lost, unless an error is
detected in any such request. Detection of an error condition always results in the
&SYS.RETCODE system variable being set to 8 and the &SYSMSG variable being set,
regardless of the type of CNMREAD issued.
It is the user's responsibility to maintain synchronization between data sent and
received across the CNM interface. Process Related Identifiers (PRIDs) contain
correlation data that can be used for synchronizing multiple CNMREADS. The
CNMCLEAR verb purges unprocessed data, and in this way can also be used to
synchronize the CNMREAD and CNMSEND verbs.
ARGS
specifies a range of generated variables. See “Frequently Occurring Operands,” at
the beginning of this section, for more information. If insufficient variables are
provided, some data is not available. Excess variables are given no value—they
are set to the null string.
RANGE=( start , end )
determines the range of variables specified by the ARGS operand. See
“Frequently Occurring Operands,” at the beginning of this section, for more
information.
SEGMENT= n
specifies the amount of data (in bytes) to be put into the variables specified.
See “Frequently Occurring Operands,” at the beginning of this section, for
more information.
VARS
input-vars-list
specifies which variables are to be used. If too few variables are specified,
data is missing; if too many variables are specified, excess variables are given
no value—they are set to the null string. Multiple variables must be enclosed
in parentheses and separated by commas.