StorageTek Host Software Component 6 User Manual

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Chapter 3. HSC Control Statements and HSC Start Procedure   133
1st ed., 6/30/04 - 312579601
 
Tape Request Definition (TREQDEF) Command and Control Statement
The TREQDEF command and control statement is used to specify the definition data set 
that contains tape request (TAPEREQ) parameter statements. (Refer to “Tape Request 
(TAPEREQ) Control Statement” on page 118 fo
r details on syntax and parameters.) The 
data set must be a sequential or a partitioned data set (PDS) with any valid record format 
(RECFM). Also, the definition data set must contain one or more TAPEREQ statements. 
The TREQDEF statement may be specified in the HSC PARMLIB, or it may be issued as 
an operator command to dynamically load or reload tape request parameters. (Refer to 
“PARMLIB Control Statements” on page 83 for an explanation of PARMLIB.) If a 
definition file is changed by a TREQDEF operator command, and if the change is to be 
permanent, you must update PARMLIB before restarting the HSC.
If the definition file is to be modified for a given shift or application, remember that the 
new definition remains in effect until another definition is loaded or the HSC is recycled. 
The definition file then reverts to the PARMLIB specification. Thus, TREQDEF can be 
used to temporarily change a definition file. 
Definition commands issued on one host are in effect only on that host. If different hosts 
use the same definition data set, then the tape request parameter statements are shared by 
those hosts. 
Notes:  
 1. When the TREQDEF command is issued, if the definition data set contains errors, an 
HSC message provides the parameter in error, a description of the problem, and the 
line number where the error occurred. If the definition data set contains errors, none 
of the attributes specified in the TAPEREQ control statement(s) will be loaded (put 
into effect), which may cause data sets to be created on the wrong type of media and 
incorrect devices to be allocated. Message SLS1627I is displayed if errors are 
encountered. If 50 errors are encountered, the remainder of the data set is not 
checked. Correct the problem and reissue the command. 
 2. The TREQDEF command and control statement executes at both base and full 
service levels of the HSC. 
 3. If you issue multiple TREQDEF statements, the last one processed is currently 
active. You can determine which TREQDEF statement is active by entering the 
Display TREQDEF command. 
TREQDEF