Service routines

Name_addr

The fullword address of the name of the module to load (input parameter).

Name_length

A fixed binary(31) length of the module name (input parameter).

User_word

A fullword user field (input parameter).

Load_point

Either zero (0), or the address where the @LOAD routine is to store the load point address of the loaded routine (input and output parameter).

Entry_point

The fullword entry point address of the loaded routine (output parameter).

Module_size

The fixed binary(31) size of the module that was loaded (output parameter).

Return code

The fullword return code from load (output).

Reason code

The fullword reason code from load (output). The return and reason codes are listed in Table 1.

Table 1. Return and reason codes from load (output)

Return code	Reason code	Description
0	0	Successful
0	12	Successful; loaded using SVC8
4	4	Unsuccessful; module loaded above the line when in AMODE(24)
8	4	Unsuccessful; load failed
16	4	Unsuccessful; uncorrectable error occurred

Name_addr

The fullword address of the module name to be deleted (input parameter).

Name_length

A fixed binary(31) length of module name (input parameter).

User_word

A fullword user field (input parameter).

Rsvd_word

A fullword reserved for future use (input parameter); must be zero.

Return code

The return code from delete service (output).

Reason code

The reason code from delete service (output). The return and reason codes are listed in Table 2.

Table 2. Return and reason codes from delete service (output)

Return code	Reason code	Description
0	0	Successful
8	4	Unsuccessful; delete failed
16	4	Unsuccessful; uncorrectable error occurred

Amount

A fixed binary(31) amount of storage requested (input parameter).

Subpool_no

A fixed binary(31) subpool number 0-127 (input parameter). Language Environment allocates storage from the process-level storage pools.

User word

A fullword user field (input parameter).

Flags

A fullword flag area (input parameter), as shown in the following table. The remaining flag bits are reserved for future use and must be zero.

Bit	Setting	Description
Zero	ON	The storage required must be allocated below the 16 MB line.
	OFF	The storage required can be allocated anywhere.
One	ON	The storage required was requested to be backed by 1 MB pages. This setting might be ignored.
	OFF	The storage required was requested to be backed by the default 4 KB pages.

Stg_address

The fullword address of the storage obtained or zero (output parameter).

Obtained

A fixed binary(31) number of bytes obtained (output parameter).

Return code

The return code from @GETSTORE service (output parameter).

Reason code

The reason code from the @GETSTORE service (output parameter).

Amount

The fixed binary(31) amount of storage to free (input parameter).

Subpool_no

The fixed binary(31) subpool number 0-127 (input parameter). Language Environment allocates storage from the process-level storage pools.

User word

A fullword user field (input parameter).

Stg_address

The fullword address of the storage to free (input parameter).

Return code

The return code from the @FREESTORE service (output).

Reason code

The reason code from the @FREESTORE service (output).

Handler_addr

During an initialization call, this parameter contains the address of the Language Environment® condition handler. During a termination call, this parameter contains a pointer to a fullword field containing zeroes.

Environment_token

A fullword Recovery Environment token (input). This token is different from the Preinitialization environment token used with CEEPIPI calls.

User_word

A fullword user field (input parameter)

Abend_flags

A fullword flag area containing abend flags (input)

Check_flags

A fullword flag area containing program check flags (input)

Return code

The return code from the @EXCEPRTN service (output).

Reason code

The reason code from the @EXCEPRTN service (output).

The exception router is responsible for trapping and routing exceptions. These are the services typically obtained via the ESTAE and ESPIE macros.

During initialization, Language Environment puts the address of the Language Environment condition handler in the first field of the above parameter list, and sets the environment token field to a value that must be passed on to the Language Environment condition handler. It also sets abend and check flags as appropriate, and then calls your exception router to establish an exception handler.

  dcl
   1 abendflags,
     2 system,
       3 abends bit(1),  /* control for system abends desired  */
       3 rsrv1  bit(15), /* reserved                           */
     2 user,
       3 abends bit(1),  /* control for user abends desired    */
       3 rsrv2  bit(15); /* reserved                           */

       1 checkflags,
         2 type,
           3 reserved3             bit(1),
           3 operation             bit(1),
           3 privileged_operation  bit(1),
           3 execute               bit(1),
           3 protection            bit(1),
           3 addressing            bit(1),
           3 specification         bit(1),
           3 data                  bit(1),
           3 fixed_overflow        bit(1),
           3 fixed_divide          bit(1),
           3 decimal_overflow      bit(1),
           3 decimal_divide        bit(1),
           3 exponent_overflow     bit(1),
           3 exponent_underflow    bit(1),
           3 significance          bit(1),
           3 float_divide          bit(1),
         2 reserved4             bit(16);

During termination, the exception router is invoked with the condition handler address (first parameter) set to zero to de-establish the exit (if it was established during initialization).

When a nested enclave is created, Language Environment calls the exception router to establish another exception handler exit, and then makes a call to de-establish it when the nested enclave terminates. If an exception occurs while the second exit is active, special processing is performed. Depending on what this second exception is, either the first exception will not be retried, or processing will continue on the first exception by requesting retry for the second exception.

If the Language Environment condition handler determines that execution should resume for an exception, it will set the SDWA with SETRP and return with return/reason codes 4/0. Execution will resume in library code or in user code, depending on what the exception was.

The exception handler must be capable of restoring all the registers from the SDWA when control is given to the retry routine. The ESPIE and ESTAE services are capable of accomplishing this.

If an exception occurs while the exception handler is in control before another exception handler exit has been stacked, the exception handler should assume that the exception could not be handled and that the environment for the program (thread) is damaged. In this case, the exception handler should force termination of the preinitialized environment.