VMS Help System Services, $GETQUI *Conan The Librarian (sorry for the slow response - running on an old VAX) |
Returns information about queues and the jobs initiated from those queues. The $GETQUI service completes asynchronously; for synchronous completion, use the Get Queue Information and Wait ($GETQUIW) service. For additional information about system service completion, refer to the Synchronize ($SYNCH) service. Format SYS$GETQUI [efn] ,func [,context] [,itmlst] [,iosb] [,astadr] [,astprm] C Prototype int sys$getqui (unsigned int efn, unsigned short int func, unsigned int *context, void *itmlst, struct _iosb *iosb, void (*astadr)(__unknown_params), int astprm); Arguments efn OpenVMS usage:ef_number type: longword (unsigned) access: read only mechanism: by value Number of the event flag to be set when $GETQUI completes. The efn argument is a longword containing this number; however, $GETQUI uses only the low-order byte. The efn argument is optional. When the request is queued, $GETQUI clears the specified event flag (or event flag 0 if efn was not specified). Then, when the operation completes, $GETQUI sets the specified event flag (or event flag 0). func OpenVMS usage:function_code type: word (unsigned) access: read only mechanism: by value Function code specifying the function that $GETQUI is to perform. The func argument is a word containing this function code. The $QUIDEF macro defines the names of each function code. You can specify only one function code in a single call to $GETQUI. Most function codes require or allow for additional information to be passed in the call. You pass this information by using the itmlst argument, which specifies a list of one or more item descriptors. Each item descriptor in turn specifies an item code, which either describes the specific information to be returned by $GETQUI, or otherwise affects the action designated by the function code. You can use wildcard mode to make a sequence of calls to $GETQUI to get information about all characteristics, form definitions, queues, or jobs contained in the system job queue file. Refer to the OpenVMS System Services Reference Manual for information on using wildcard mode. context OpenVMS usage:context type: longword (unsigned) access: modify mechanism: by reference Address of a longword containing the number of a context stream for this call to the $GETQUI system service. If the argument is unspecified or 0, the service uses the default context stream (#0). To generate a new context stream, the specified longword must contain -1. $GETQUI then modifies the longword to hold the context number for that stream of operation. The context is marked with the caller's mode (user, supervisor, executive, or kernel). Any attempt to use that context in successive calls is checked and no call from a mode outside the recorded mode is allowed access. To clean up a context, make a $GETQUI call using the QUI$_CANCEL_ OPERATION function code and specify the address of the context number as the context argument. itmlst OpenVMS usage:item_list_3 type: longword (unsigned) access: read only mechanism: by reference Item list supplying information to be used in performing the function specified by the func argument. The itmlst argument is the address of the item list. The item list consists of one or more item descriptors, each of which contains an item code. The item list is terminated by an item code of 0 or by a longword of 0. Refer to the OpenVMS System Services Reference Manual to view the item code diagram and descriptor fields table. iosb OpenVMS usage:io_status_block type: quadword (unsigned) access: write only mechanism: by reference I/O status block into which $GETQUI writes the completion status after the requested operation has completed. The iosb argument is the address of the I/O status block. At request initiation, $GETQUI sets the value of the quadword I/O status block to 0. When the requested operation has completed, $GETQUI writes a condition value in the first longword of the I/O status block. It writes the value 0 into the second longword; this longword is unused and reserved for future use. The condition values returned by $GETQUI in the I/O status block are condition values from the JBC facility, which are defined by the $JBCMSGDEF macro. The condition values returned from the JBC facility are listed in the section Condition Values Returned in the I/O Status Block section. Though this argument is optional, Compaq strongly recommends that you specify it, for the following reasons: o If you are using an event flag to signal the completion of the service, you can test the I/O status block for a condition value to be sure that the event flag was not set by an event other than service completion. o If you are using the $SYNCH service to synchronize completion of the service, the I/O status block is a required argument for $SYNCH. o The condition value returned in R0 and the condition value returned in the I/O status block provide information about different aspects of the call to the $GETQUI service. The condition value returned in R0 gives you information about the success or failure of the service call itself; the condition value returned in the I/O status block gives you information about the success or failure of the service operation. Therefore, to accurately assess the success or failure of the call to $GETQUI, you must check the condition values returned in both R0 and the I/O status block. astadr OpenVMS usage:ast_procedure type: procedure value access: call without stack unwinding mechanism: by reference AST service routine to be executed when $GETQUI completes. The astadr argument is the address of this routine. If specified, the AST routine executes at the same access mode as the caller of $GETQUI. astprm OpenVMS usage:user_parm type: longword (unsigned) access: read only mechanism: by value AST parameter to be passed to the AST service routine specified by the astadr argument. The astprm argument is this longword parameter.
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