SSDA mapping

Table 1. Structure SSDA
`Offset Dec`	`Offset Hex`	`Type`	`Len`	`Name(Dim)`	`Description`
`0`	`(0)`	`STRUCTURE`	`28`	`SSDA`	`DATA MANAGEMENT FUNCTION`
`0`	`(0)`	`SIGNED`	`2`	`SSDALEN`	`LENGTH OF SSDA`
`2`	`(2)`	`UNSIGNED`	`1`	`SSDAVER`	`MACRO VERSION NUMBER`
`3`	`(3)`	`BITSTRING`	`1`	`SSDARESF`	`RESTART FLAGS`
		`1... ....`		`SSDAAUTO`	`AUTO CHECKPOINT RESTART`
		`.1.. ....`		`SSDADEFR`	`DEFERRED CHECKPOINT RESTART`
		`..11 1111`		`*`	`RESERVED`
`4`	`(4)`	`ADDRESS`	`4`	`SSDABUFR`	`4K BUFFER PTR-GOTTEN BY CHECKPT AND RESTART, USED BY SUBSYSTEM OR 256 BYTE PTR-GOTTEN BY OPEN, USED BY SUBSYSTEM FOR OPEN VERIFICATION`
`8`	`(8)`	`ADDRESS`	`4`	`SSDAJFCB`	`JFCB POINTER`
`12`	`(C)`	`ADDRESS`	`4`	`SSDADEBP`	`DEB POINTER`
`16`	`(10)`	`ADDRESS`	`4`	`SSDASSCM`	`POINTER TO SUBSYSTEM INFORMATION`
`20`	`(14)`	`ADDRESS`	`4`	`SSDADSAB`	`DSAB POINTER`
`24`	`(18)`	`BITSTRING`	`1`	`SSDAOCFL`	`OPEN/CLOSE FLAGS`
		`1... ....`		`SSDAOPNV`	`OPEN VERIFICATION`
		`.1.. ....`		`SSDALRNS`	`LRECL NOT AVAILABLE, DEFAULTED BY OPEN`
`25`	`(19)`	`CHARACTER`	`3`	`SSDARSV2`	`RESERVED`

Table 2. Constants for SSDA
`Len`	`Type`	`Value`	`Name`	`Description`
`2`	`DECIMAL`	`16`	`SSOBOPEN`	`OPEN FUNCTION ID`
`2`	`DECIMAL`	`17`	`SSOBCLOS`	`CLOSE FUNCTION ID`
`2`	`DECIMAL`	`18`	`SSOBCKPT`	`CHECKPOINT FUNCTION ID`
`2`	`DECIMAL`	`19`	`SSOBREST`	`RESTART FUNCTION ID`
`OPEN/CLOSE, C/R RETURN CODES (SSOBRETN)`
`4`	`DECIMAL`	`0`	`SSDMOK`	`REQUEST SUCCESSFUL YM02677`
`4`	`DECIMAL`	`4`	`SSDMFAIL`	`REQUEST UNSUCCESSFUL YM02677`
`ADDITIONAL DATA FOR THIS EXTENSION`
`1`	`DECIMAL`	`2`	`SSDACVER`	`CURRENT VERSION NUMBER`