OpenVMS System Services Reference Manual

Document revision date: 30 March 2001

OpenVMS System Services Reference Manual

Contents

Index

%%%%%%%%%%% OPCOM 30-DEC-2001 13:44:40.37 Operator _NODE$LTA5: has been enabled, username HOEBLE

The following example shows the message displayed on an operator terminal as a result of a request to display the status of that operator terminal:

%%%%%%%%%%% OPCOM 30-DEC-2001 12:11:10.48 Operator status for operator _NODE$OPA0: CENTRAL, PRINTER, TAPES, DISKS, DEVICES, CARDS, CLUSTER, SECURITY, OPER1, OPER2, OPER3, OPER4, OPER5, OPER6, OPER7, OPER8, OPER9, OPER10, OPER11, OPER12

The following example shows the message displayed on an operator terminal as a result of a user request:

%%%%%%%%%%% OPCOM 30-DEC-2001 12:57:32.25 Request 1285, from user ROSS on NODE_NAME Please mount device _NODE$DMA0:

Required Access or Privileges

OPER privilege is required for the following functions:

Enabling a terminal as an operator's terminal
Replying to or canceling a user's request
Initializing the operator communication log file

In addition, the operator must have SECURITY privilege to affect security functions.

Required Quota

None

Related Services

$ALLOC, $ASSIGN, $BRKTHRU, $BRKTHRUW, $CANCEL, $CREMBX, $DALLOC, $DASSGN, $DELMBX, $DEVICE_SCAN, $DISMOU, $GETDVI, $GETDVIW, $GETMSG, $GETQUI, $GETQUIW, $INIT_VOL, $MOUNT, $PUTMSG, $QIO, $QIOW, $SNDERR, $SNDJBC, $SNDJBCW

Condition Values Returned

SS$_NORMAL The service completed successfully.

SS$_ACCVIO The message buffer or buffer descriptor cannot be read by the caller.

SS$_BADPARAM The specified message has a length of 0 or has more than 986 bytes.

SS$_DEVNOTMBX The channel specified is not assigned to a mailbox.

SS$_INSFMEM The service was called from kernel mode or the system dynamic memory is insufficient for completing the service.

SS$_IVCHAN You specified an invalid channel number. An invalid channel number is one that is 0 or a number larger than the number of channels available.

SS$_MBFULL The mailbox used to support communication is full. Retry at a later time.

OPC$_NOPERATOR The service completed successfully; the Operator Communications Manager (OPCOM) is not running and the message will not be sent. Note that OPC$_NOPERATOR is a success status and must be tested for explicitly.

SS$_NOPRIV The process does not have the privilege to reply to or cancel a user's request; the process does not have read/write access to the specified mailbox; or the channel was assigned from a more privileged access mode.

Condition Values Returned in the Mailbox

OPC$_BLANKTAPE The service completed successfully; the operator responded with the DCL command REPLY/BLANK_TAPE=n.

OPC$_INITAPE The service completed successfully; the operator responded with the DCL command REPLY/INITIALIZE_TAPE=n.

OPC$_NOPERATOR The service completed successfully; no operator terminal was enabled to receive the message.

OPC$_RQSTCMPLTE The service completed successfully; the operator completed the request.

OPC$_RQSTPEND The service completed successfully; the operator will perform the request when possible.

OPC$_RQSTABORT The operator could not satisfy the request.

OPC$_RQSTCAN The caller canceled the request.

Examples

#1
#include <ssdef.h> #include <opcdef.h> #include <string.h> #include <descrip.h> #include <starlet.h> #include <lib$routines.h> char input_buffer[256]; /* Input buffer, if needed / / VMS descriptors: / $DESCRIPTOR(input_desc, input_buffer); $DESCRIPTOR(prompt_desc, "Request> "); struct dsc$descriptor req_desc; main(int argc, char argv[]) { int status, /* Status of system calls / length = 0; / Length of message text / struct OPC request; / Request message buffer / / Check for too many arguments on command line / if (argc > 2) return (SS$_OVRMAXARG); / See if request string present on command line... / if (argc > 1) { / It is. Compute length and copy pointer / length = strlen(argv[1]); input_desc.dsc$a_pointer = argv[1]; } / If no message present, prompt user for message text / while (length == 0) { status = lib$get_input(&input_desc, &prompt_desc, &length); if (status != SS$_NORMAL) return (status); }; if (length > 128) / Limit message length / length = 128; / to 128 characters / / Set up request buffer... / request.opc$b_ms_type = OPC$_RQ_RQST; request.opc$b_ms_target = OPC$M_NM_CENTRL; request.opc$l_ms_rqstid = 0; memcpy(&request.opc$l_ms_text, input_desc.dsc$a_pointer, length); / Set up request buffer descriptor and send message / req_desc.dsc$w_length = length + 8; req_desc.dsc$a_pointer = (char ) &request; return (sys$sndopr(&req_desc, 0)); }

#include <ssdef.h> 
#include <opcdef.h> 
#include <string.h> 
#include <descrip.h> 
#include <starlet.h> 
#include <lib$routines.h> 
 
char    input_buffer[256];      /* Input buffer, if needed */ 
 
/* VMS descriptors: */ 
$DESCRIPTOR(input_desc, input_buffer); 
$DESCRIPTOR(prompt_desc, "Request> "); 
struct dsc$descriptor req_desc; 
 
main(int argc, char *argv[]) 
{ 
    int status,                 /* Status of system calls */ 
        length = 0;             /* Length of message text */ 
    struct OPC request;         /* Request message buffer */ 
 
    /* Check for too many arguments on command line */ 
    if (argc > 2) 
        return (SS$_OVRMAXARG); 
 
    /* See if request string present on command line... */ 
    if (argc > 1) 
    { 
        /* It is.  Compute length and copy pointer */ 
        length = strlen(argv[1]); 
        input_desc.dsc$a_pointer = argv[1]; 
    } 
 
    /* If no message present, prompt user for message text */ 
    while (length == 0) 
    { 
        status = lib$get_input(&input_desc, &prompt_desc, &length); 
        if (status != SS$_NORMAL) 
            return (status); 
    }; 
 
    if (length > 128)           /* Limit message length */ 
        length = 128;           /*    to 128 characters */ 
 
    /* Set up request buffer... */ 
    request.opc$b_ms_type = OPC$_RQ_RQST; 
    request.opc$b_ms_target = OPC$M_NM_CENTRL; 
    request.opc$l_ms_rqstid = 0; 
    memcpy(&request.opc$l_ms_text, input_desc.dsc$a_pointer, length); 
 
    /* Set up request buffer descriptor and send message */ 
    req_desc.dsc$w_length = length + 8; 
    req_desc.dsc$a_pointer = (char *) &request; 
    return (sys$sndopr(&req_desc, 0)); 
}

This example allows you to build an operator request and send the request to the operator.

#2
IMPLICIT NONE ! Symbol definitions INCLUDE '($DVIDEF)' INCLUDE '($OPCDEF)' ! Structures for SNDOPR STRUCTURE /MESSAGE/ UNION MAP BYTE TYPE, 2 ENABLE(3) INTEGER4 MASK INTEGER2 OUNIT CHARACTER14 ONAME END MAP MAP CHARACTER24 STRING END MAP END UNION END STRUCTURE RECORD /MESSAGE/ MSGBUF ! Length of MSGBUF.ONAME INTEGER4 ONAME_LEN ! Status and routines INTEGER4 STATUS, 2 LIB$GETDVI, 2 SYS$SNDOPR ! Type MSGBUF.TYPE = OPC$_RQ_TERME ! Enable MSGBUF.ENABLE(1) = 1 ! Operator type MSGBUF.MASK = OPC$M_NM_OPER1 ! Terminal unit number STATUS = LIB$GETDVI (DVI$_UNIT, 2 , 2 'SYS$OUTPUT', 2 MSGBUF.OUNIT,,) IF (.NOT. STATUS) CALL LIB$SIGNAL (%VAL(STATUS)) ! Terminal name STATUS = LIB$GETDVI (DVI$_FULLDEVNAM, 2 , 2 'SYS$OUTPUT',, 2 MSGBUF.ONAME, 2 ONAME_LEN) IF (.NOT. STATUS) CALL LIB$SIGNAL (%VAL(STATUS)) ! Remove unit number from ONAME and set up counted string ONAME_LEN = ONAME_LEN - 3 MSGBUF.ONAME(2:ONAME_LEN+1) = MSGBUF.ONAME(1:ONAME_LEN) MSGBUF.ONAME(1:1) = CHAR(ONAME_LEN) ! Call $SNDOPR STATUS = SYS$SNDOPR (MSGBUF.STRING,) IF (.NOT. STATUS) CALL LIB$SIGNAL(%VAL(STATUS)) END

IMPLICIT NONE 
 
        ! Symbol definitions 
        INCLUDE '($DVIDEF)' 
        INCLUDE '($OPCDEF)' 
 
        ! Structures for SNDOPR 
        STRUCTURE /MESSAGE/ 
         UNION 
          MAP 
           BYTE TYPE, 
        2       ENABLE(3) 
           INTEGER*4 MASK 
           INTEGER*2 OUNIT 
           CHARACTER*14 ONAME 
          END MAP 
          MAP 
           CHARACTER*24 STRING 
          END MAP 
         END UNION 
        END STRUCTURE 
        RECORD /MESSAGE/ MSGBUF 
        ! Length of MSGBUF.ONAME 
        INTEGER*4 ONAME_LEN 
 
        ! Status and routines 
        INTEGER*4 STATUS, 
        2         LIB$GETDVI, 
        2         SYS$SNDOPR 
 
        ! Type 
        MSGBUF.TYPE = OPC$_RQ_TERME 
        ! Enable 
        MSGBUF.ENABLE(1) = 1 
        ! Operator type 
        MSGBUF.MASK = OPC$M_NM_OPER1 
        ! Terminal unit number 
        STATUS = LIB$GETDVI (DVI$_UNIT, 
        2                    , 
        2                    'SYS$OUTPUT', 
        2                    MSGBUF.OUNIT,,) 
        IF (.NOT. STATUS) CALL LIB$SIGNAL (%VAL(STATUS)) 
        ! Terminal name 
        STATUS = LIB$GETDVI (DVI$_FULLDEVNAM, 
        2                    , 
        2                    'SYS$OUTPUT',, 
        2                    MSGBUF.ONAME, 
        2                    ONAME_LEN) 
        IF (.NOT. STATUS) CALL LIB$SIGNAL (%VAL(STATUS)) 
        ! Remove unit number from ONAME and set up counted string 
        ONAME_LEN = ONAME_LEN - 3 
        MSGBUF.ONAME(2:ONAME_LEN+1) = MSGBUF.ONAME(1:ONAME_LEN) 
        MSGBUF.ONAME(1:1) = CHAR(ONAME_LEN) 
        ! Call $SNDOPR 
        STATUS = SYS$SNDOPR (MSGBUF.STRING,) 
        IF (.NOT. STATUS) CALL LIB$SIGNAL(%VAL(STATUS)) 
        END

This Compaq Fortran for OpenVMS program enables the current terminal to receive OPER1 operator messages.

$START_ALIGN_FAULT_REPORT (Alpha Only)

On Alpha systems, initializes user image alignment fault reporting.

Format

SYS$START_ALIGN_FAULT_REPORT report_method ,report_buffer ,buffer_length

C Prototype

int sys$start_align_fault_report (int report_method, void *report_buffer, int buffer_length);

Arguments

report_method

OpenVMS usage: longword_signed

type: longword (signed)

access: read

mechanism: by value

Method by which image alignment faults are to be reported.
The following table shows valid values for the report_method argument:

Value Meaning

AFR$C_BUFFERED Alignment fault PCs and fault addresses are saved in a user-supplied buffer.

AFR$C_EXCEPTION Alignment faults are elevated to user mode exceptions.

report_buffer

OpenVMS usage: address

type: longword (unsigned)

access: read

mechanism: by reference

The 32-bit address of the buffer into which to write the fault data. The report_buffer argument is needed only if the value of the report_method argument is AFR$C_BUFFERED.
buffer_length

OpenVMS usage: byte count

type: longword (signed)

access: read

mechanism: by value

Length of the buffer specified in the report_buffer argument.
The buffer must have a minimum size of AFR$K_USER_LENGTH + 32. However, a larger buffer allows for more information to be collected.

Value	Meaning
AFR$C_BUFFERED	Alignment fault PCs and fault addresses are saved in a user-supplied buffer.
AFR$C_EXCEPTION	Alignment faults are elevated to user mode exceptions.

Description

The Start Alignment Fault Reporting service initializes user image alignment fault reporting.
The $START_ALIGN_FAULT_REPORT service allows the user to gather alignment fault data for one image. Reporting is enabled for the life of the image. When the image terminates, the alignment fault reporting is disabled.
User alignment fault data can be written to a buffer or broadcast as an informational exception message.
If the AFR$C_BUFFERED value is given in the report_method buffer, alignment fault PCs and fault addresses are saved in a user-supplied buffer.
The following diagram illustrates the format in which user alignment fault data is stored in the buffer:

If the AFR$C_EXCEPTION value is given in the report_method argument, alignment faults are elevated to user mode exceptions. These exceptions can be trapped in a handler; otherwise, an informational exception message might be broadcast and the program continues to execute.

Required Access or Privileges

None

Required Quota

None

Related Services

$GET_ALIGN_FAULT_DATA, $GET_SYS_ALIGN_FAULT_DATA, $INIT_SYS_ALIGN_FAULT_REPORT, $PERM_DIS_ALIGN_FAULT_REPORT, $PERM_REPORT_ALIGN_FAULT, $STOP_ALIGN_FAULT_REPORT, $STOP_SYS_ALIGN_FAULT_REPORT

Condition Values Returned

SS$_NORMAL The service completed successfully.

SS$_ACCVIO The buffer specified in the report_buffer argument is not accessible.

SS$_AFR_ENABLED The service has already been called for this image.

SS$_ARG_GTR_32_BITS The report buffer's virtual address lies in 64-bit virtual address space.

SS$_ALIGN The buffer specified in the report_buffer argument is not quadword aligned.

SS$_BADPARAM The buffer size is smaller than that defined by the AFR$K_USER_LENGTH + 32 symbol.

Example


#include <afrdef> #include <stdio> #include <ssdef> #define USER_BUFFER_ITEMS 10 #define GET_BUFFER_SIZE USER_BUFFER_ITEMSAFR$K_USER_LENGTH #define SAVE_BUFFER_SIZE 128+64 #define fault_pc afr$l_fault_pc_l #define fault_va afr$l_fault_va_l static int usr_buff_len; static char usr_buff; static int rep_method; void cause_af() { int addr; int ptr; int arr[2]; addr = (int) &arr[0]; ptr = (int ) ++addr; ptr = 1; / cause alignment fault / } main() { int i; char get_buffer[GET_BUFFER_SIZE]; struct afrdef data_item; int offset; int status; int return_size; rep_method = AFR$C_BUFFERED; usr_buff_len = SAVE_BUFFER_SIZE; usr_buff = (char )malloc (usr_buff_len); if(( status = sys$start_align_fault_report(rep_method, usr_buff, usr_buff_len)) != SS$_NORMAL) return(status); for (i=0;i<USER_BUFFER_ITEMS;i++) cause_af(); while (((status = sys$get_align_fault_data (get_buffer, GET_BUFFER_SIZE, &return_size)) > 0) && (return_size > 0)) { / got some data, print it / offset = 0; while (offset < return_size) { data_item = (struct afrdef )(&get_buffer[offset]); printf ("Alignment fault at PC = %8.8X, VA = %8.8X\n", data_item->fault_pc, data_item->fault_va); offset += AFR$K_USER_LENGTH; } } return (status); }

#include <afrdef>  
#include <stdio> 
#include <ssdef> 
 
#define USER_BUFFER_ITEMS  10 
#define GET_BUFFER_SIZE    USER_BUFFER_ITEMS*AFR$K_USER_LENGTH 
#define SAVE_BUFFER_SIZE   128+64 
 
#define fault_pc afr$l_fault_pc_l 
#define fault_va afr$l_fault_va_l 
 
static int usr_buff_len; 
static char *usr_buff; 
static int rep_method; 
 
 
void 
cause_af() 
{ 
  int     addr; 
  int     *ptr; 
  int    arr[2]; 
 
  addr = (int) &arr[0]; 
  ptr = (int *) ++addr; 
  *ptr = 1;    /* cause alignment fault */ 
} 
 
 
main() 
{ 
  int            i; 
  char           get_buffer[GET_BUFFER_SIZE]; 
  struct afrdef  *data_item; 
  int            offset; 
  int            status; 
  int            return_size; 
 
  rep_method = AFR$C_BUFFERED; 
  usr_buff_len = SAVE_BUFFER_SIZE; 
  usr_buff = (char *)malloc (usr_buff_len); 
  if(( status = sys$start_align_fault_report(rep_method, usr_buff, 
               usr_buff_len)) 
      != SS$_NORMAL) return(status); 
 
  for (i=0;i<USER_BUFFER_ITEMS;i++) 
    cause_af(); 
 
  while (((status = sys$get_align_fault_data (get_buffer, 
                GET_BUFFER_SIZE, 
                &return_size)) > 0) && 
         (return_size > 0)) { 
    /* got some data, print it */ 
    offset = 0; 
    while (offset < return_size) { 
      data_item = (struct afrdef *)(&get_buffer[offset]); 
      printf ("Alignment fault at PC = %8.8X, VA = %8.8X\n", 
        data_item->fault_pc, data_item->fault_va); 
      offset += AFR$K_USER_LENGTH; 
    } 
  } 
 
  return (status); 
}

This example shows how to use the $START_ALIGN_FAULT_REPORT service to initialize user image alignment fault reporting on Alpha systems.

$START_TRANS

Starts a new transaction.

Format

SYS$START_TRANS [efn] ,[flags] ,iosb [,[astadr] ,[astprm] ,[tid] ,[timout] ,[acmode]]

C Prototype

int sys$start_trans (unsigned int efn, unsigned int flags, struct _iosb *iosb,...);

Arguments

efn

OpenVMS usage: ef_number

type: longword (unsigned)

access: read only

mechanism: by value

Number of the event flag that is set when the service completes. If this argument is omitted, event flag 0 is set.
flags

OpenVMS usage: mask_longword

type: longword (unsigned)

access: read only

mechanism: by value

Flags specifying options for the service. The flags argument is a longword bit mask in which each bit corresponds to an option flag. The $DDTMDEF macro defines symbolic names for these option flags. All undefined bits must be 0. If this argument is omitted, no flags are set.
The flags currently defined are shown in the following table:

Flag Description

DDTM$M_NONDEFAULT Set this flag if you do not want the new transaction to be the default transaction of the calling process.
If this flag is clear, the new transaction becomes the default transaction of the calling process. An error is returned if this flag is clear and the calling process already has a default transaction.

DDTM$M_PROCESS Set this flag if you do not want the DECdtm transaction manager to try to abort the transaction if the current image terminates.
If this flag is clear, when the current image terminates (normally or abnormally), the DECdtm transaction manager will abort the transaction if it has not already committed.
An error is returned if this flag is set and the caller is in user mode.

DDTM$M_SYNC Set this flag to specify that successful synchronous completion is to be indicated by returning SS$_SYNCH. When SS$_SYNCH is returned, the AST routine is not called, the event flag is not set, and the I/O status block is not filled in.

iosb

OpenVMS usage: io_status_block

type: quadword (unsigned)

access: write only

mechanism: by reference

I/O status block in which the completion status of the service is returned as a condition value. See the Condition Values Returned section.
The following diagram shows the structure of the I/O status block:

Flag	Description
DDTM$M_NONDEFAULT	Set this flag if you do not want the new transaction to be the default transaction of the calling process. If this flag is clear, the new transaction becomes the default transaction of the calling process. An error is returned if this flag is clear and the calling process already has a default transaction.
DDTM$M_PROCESS	Set this flag if you do not want the DECdtm transaction manager to try to abort the transaction if the current image terminates. If this flag is clear, when the current image terminates (normally or abnormally), the DECdtm transaction manager will abort the transaction if it has not already committed. An error is returned if this flag is set and the caller is in user mode.
DDTM$M_SYNC	Set this flag to specify that successful synchronous completion is to be indicated by returning SS$_SYNCH. When SS$_SYNCH is returned, the AST routine is not called, the event flag is not set, and the I/O status block is not filled in.

astadr

OpenVMS usage:	ast_procedure
type:	procedure value
access:	call without stack unwinding
mechanism:	by reference

AST routine that is executed when the service completes. The astadr argument is the address of this routine. This routine is executed in the access mode of the caller.

astprm

OpenVMS usage:	user_arg
type:	longword (unsigned)
access:	read only
mechanism:	by value

AST parameter that is passed to the AST routine specified by the astadr argument.

tid

OpenVMS usage:	transaction_id
type:	octaword (unsigned)
access:	write only
mechanism:	by reference

Address of an octaword in which the service returns the identifier of the new transaction.

timout

OpenVMS usage:	date_time
type:	quadword (unsigned)
access:	read only
mechanism:	by reference

Timeout for the new transaction. This is the time at which the DECdtm transaction manager is to abort the transaction if the transaction has not already committed.

The time value is a binary number, in units of 100 nanoseconds.

A positive time value specifies an offset from the system base time. The system base time is 00:00 hours November 17, 1858.

A negative time value specifies an offset from the current time to some time in the future.

The transaction is aborted at the next timer interval if you specify either a zero time value or any time in the past.

If this argument is omitted, the new transaction has no timeout.

acmode

OpenVMS usage:	access_mode
type:	longword (unsigned)
access:	read only
mechanism:	by value

The least privileged access mode that the calling process must be in to end the transaction by calling $END_TRANS. Note that the calling process can end the transaction by calling $ABORT_TRANS from any access mode.

The access mode that the calling process must be in to end the transaction by calling $END_TRANS is whichever is the least privileged of the following:

The access mode of the caller
The access mode specified by the acmode argument

If the acmode argument is omitted, it defaults to the access mode of the caller.

Description

The Start Transaction service starts a new transaction that is to be coordinated by the DECdtm distributed transaction manager.
$START_TRANS creates a unique transaction identifier for the new transaction. The same identifier can never be created by any other call to $START_TRANS on any node.
Each process can have a default transaction. This is the transaction that is assumed when the process:

Invokes resource manager operations without specifying a transaction identifier, for resource managers such as RMS Journaling that support default transactions
Calls $END_TRANS or $ABORT_TRANS without specifying a tid argument

By default, the new transaction becomes the default transaction of the calling process. If you want to start a new transaction and the calling process already has a default transaction, set the DDTM$M_NONDEFAULT flag.
Required Access or Privileges

None
Required Quotas

ASTLM, BYTLM
Related Services

$ABORT_TRANS, $ABORT_TRANSW, $END_TRANS, $END_TRANSW, $START_TRANSW

Condition Values Returned

SS$_NORMAL If this was returned in R0, the request was successfully queued. If it was returned in the I/O status block, the service completed successfully.

SS$_SYNCH The service completed successfully and synchronously (returned only if the DDTM$M_SYNC flag is set).

SS$_ACCVIO An argument was not accessible by the caller.

SS$_ALCURTID An attempt was made to start a default transaction (the DDTM$M_NONDEFAULT flag was clear) when the calling process already had a default transaction.

SS$_BADPARAM Either the DDTM$M_NONDEFAULT flag was set and the tid argument was omitted, or the options flags were invalid.

SS$_CURTIDCHANGE The DDTM$M_NONDEFAULT flag was clear and a call to change the default transaction of the calling process was in progress.

SS$_EXASTLM The process AST limit (ASTLM) was exceeded.

SS$_EXQUOTA The job buffered I/O byte limit quota (BYTLM) was exceeded.

SS$_ILLEFC The event flag number was invalid.

SS$_INSFARGS Not enough arguments were supplied.

SS$_INSFMEM There was insufficient system dynamic memory for the operation.

SS$_NOLOG The local node did not have a transaction log.

SS$_TPDISABLED The TP_SERVER process was not running on the local node.

SS$_WRONGACMODE The DDTM$M_PROCESS flag was set and the caller was in user mode.

Contents

Index

privacy and legal statement

4527PRO_099.HTML

SS$_NORMAL	The service completed successfully.
SS$_ACCVIO	The message buffer or buffer descriptor cannot be read by the caller.
SS$_BADPARAM	The specified message has a length of 0 or has more than 986 bytes.
SS$_DEVNOTMBX	The channel specified is not assigned to a mailbox.
SS$_INSFMEM	The service was called from kernel mode or the system dynamic memory is insufficient for completing the service.
SS$_IVCHAN	You specified an invalid channel number. An invalid channel number is one that is 0 or a number larger than the number of channels available.
SS$_MBFULL	The mailbox used to support communication is full. Retry at a later time.
OPC$_NOPERATOR	The service completed successfully; the Operator Communications Manager (OPCOM) is not running and the message will not be sent. Note that OPC$_NOPERATOR is a success status and must be tested for explicitly.
SS$_NOPRIV	The process does not have the privilege to reply to or cancel a user's request; the process does not have read/write access to the specified mailbox; or the channel was assigned from a more privileged access mode.

OPC$_BLANKTAPE	The service completed successfully; the operator responded with the DCL command REPLY/BLANK_TAPE=n.
OPC$_INITAPE	The service completed successfully; the operator responded with the DCL command REPLY/INITIALIZE_TAPE=n.
OPC$_NOPERATOR	The service completed successfully; no operator terminal was enabled to receive the message.
OPC$_RQSTCMPLTE	The service completed successfully; the operator completed the request.
OPC$_RQSTPEND	The service completed successfully; the operator will perform the request when possible.
OPC$_RQSTABORT	The operator could not satisfy the request.
OPC$_RQSTCAN	The caller canceled the request.

OpenVMS usage:	longword_signed
type:	longword (signed)
access:	read
mechanism:	by value

OpenVMS usage:	address
type:	longword (unsigned)
access:	read
mechanism:	by reference

OpenVMS usage:	byte count
type:	longword (signed)
access:	read
mechanism:	by value

OpenVMS usage:	ef_number
type:	longword (unsigned)
access:	read only
mechanism:	by value

OpenVMS usage:	mask_longword
type:	longword (unsigned)
access:	read only
mechanism:	by value

OpenVMS usage:	io_status_block
type:	quadword (unsigned)
access:	write only
mechanism:	by reference

SS$_NORMAL	If this was returned in R0, the request was successfully queued. If it was returned in the I/O status block, the service completed successfully.
SS$_SYNCH	The service completed successfully and synchronously (returned only if the DDTM$M_SYNC flag is set).
SS$_ACCVIO	An argument was not accessible by the caller.
SS$_ALCURTID	An attempt was made to start a default transaction (the DDTM$M_NONDEFAULT flag was clear) when the calling process already had a default transaction.
SS$_BADPARAM	Either the DDTM$M_NONDEFAULT flag was set and the tid argument was omitted, or the options flags were invalid.
SS$_CURTIDCHANGE	The DDTM$M_NONDEFAULT flag was clear and a call to change the default transaction of the calling process was in progress.
SS$_EXASTLM	The process AST limit (ASTLM) was exceeded.
SS$_EXQUOTA	The job buffered I/O byte limit quota (BYTLM) was exceeded.
SS$_ILLEFC	The event flag number was invalid.
SS$_INSFARGS	Not enough arguments were supplied.
SS$_INSFMEM	There was insufficient system dynamic memory for the operation.
SS$_NOLOG	The local node did not have a transaction log.
SS$_TPDISABLED	The TP_SERVER process was not running on the local node.
SS$_WRONGACMODE	The DDTM$M_PROCESS flag was set and the caller was in user mode.