IEASVCxx.ini

The IEASVCxx.ini file contains definitions for replacement Supervisor Call (SVC) routines. This allows you to customize the Tachyon Operating System by installing your own SVC routines. Chapter 8 describes how to create your own SVC routines.

The suffixes for the IEASVCxx.ini files are specified in the SVC parameter of the IEASYSxx.ini file.

Each IEASVCxx.ini file may contain multiple statements and comments. A comment is allowed whenever a blank is allowed. Comments start with /* and end with */. Comments may not be nested.

Each statement must start on a separate line from previous statements. Each statement has a type of SVCPARM and must be followed by parameters that define the SVC routine. More than one parameter may be specified on each line of the statement. Parameters may be continued on to a new line by coding the parameter up to column 72 and continuing in column 1 of the next line. Each parameter value must be enclosed in parentheses which must immediately follow the parameter name. The statement parameters are:

SVC

The SVC parameter is required. It specifies the number of the SVC routine to be replaced. The SVC parameter value must be a number from 0 to 255. If it is 109, 116, 122 or 137, the ESR parameter is also required.

ESR

The ESR parameter is required if the SVC parameter value is 109, 116, 122 or 137. It is not allowed if the SVC parameter value is any other number. The ESR parameter specifies the number of the Extended SVC Routine to be replaced. The ESR parameter value must be a number in the following range, depending on the SVC parameter value:

SVC	ESR
109	0 - 255
116	0 - 14
122	0 - 16
137	0 - 5

TYPE

The TYPE parameter is required. It specifies the type of the SVC routine to be replaced. The TYPE parameter value must be one of: 0, 1, 2, 3, 4 or 6.

EP

The EP specifies the module name containing the SVC routine. The module must be in SYS1.LPALIB or one of the data sets listed in the LPALSTxx.ini configuration files. If not specified, the default for EP depends on the TYPE and ESR parameter values. For ESR modules, the default EP is IGCX00nnn, where nnn is the ESR parameter value in decimal. For non-ESR modules, the default EP is IGCnnn for TYPE 0, 1, 2 and 6 routines and IGC00nnn for TYPE 3 and 4 routines.

APF

The APF parameter specifies whether or not the SVC routine may only be called by authorized callers. If APF(YES) is specified, the SVC routine may only be called if the caller is in supervisor state, key 0-7 or if the caller is APF authorized. If APF(NO) is specified or if the APF parameter is not specified, the SVC routine may be called by both authorized and unauthorized callers.

AR

The AR parameter specifies whether or not the SVC routine may be called by callers in Access Register (AR) mode. If AR(YES) is specified, the SVC may be called in either AR or Primary Space mode. If AR(NO) is specified or if the AR parameter is not specified, the SVC routine may only be called in Primary Space mode.

Example IEASVCxx.ini file:

/* Sample IEASVC00.ini file */
   /* Define ESTAE as a dummy routine */
      SVCPARM SVC(60) TYPE(1) EP(IEFBR14) AR(YES)
   /* Define OUTADD and OUTDEL as dummy routines. */
      SVCPARM SVC(109) ESR(33) TYPE(1) EP(IEFBR14)