bdfp1m2oProgramming Concepts and Reference

DBTRD-Read a Subfile from an Input Tape to Main Storage

Use this macro to read a subfile from an input tape or sequential data set to main storage.

Format




REF=dsectvv
specifies the file or subfile that you want to access, where dsectvv is the DSECT name and an optional 2-character version.

REF=refname
specifies the file or subfile that you want to access, where refname is a label that references the DSECT name in one of the following formats:

refname
is the label of an 8-byte field that contains the 6-byte DSECT name and an optional 2-character version.

A/refname
is the label of a 4-byte field that contains the storage address of the DSECT name and an optional 2-character version.

FILE=dsect
specifies the file or subfile that you want to access, where dsect is the DSECT name.

R3=address
specifies the location of the SW00SR slot for this subfile, where address is the label of a field that contains the address of the SW00SR slot. Register 3 will be loaded with this address.
Note:
Do not use this parameter; it is provided only for migration purposes. Use the REF parameter to specify the file that you want to access.

TAPE=tapename
specifies the tape from which you want to read the data, where tapename is a 3-character symbolic tape name or sequential data set.

ERROR=spmlbl
branches to the specified location if a serious error is detected when processing the macro, where spmlbl is a TPFDF structured program macro (SPM) label defined with the #LOCA macro. See TPFDF and TPF Structured Programming Macros for more information about the #LOCA macro. See Identifying Return Indicators and Errors for more information about serious errors.

ERRORA=asmlbl
branches to the specified location if a serious error is detected when processing the macro, where asmlbl is an assembler label. See Identifying Return Indicators and Errors for more information about serious errors.

REG=register
specifies a register in which to return the address of the prime block (this address is contained in SW00SR field SW00PCA).

SUFFIX=char
allows you to use the same DSECT to map two different areas of storage, where char is the suffix character.

Entry Requirements

None.

Normal Return

None.

Error Return

 See Identifying Return Indicators and Errors for information about how to check the error indicators. 

Programming Considerations

Examples

The following example reads subfile GR54DF from tape TST to main storage.

DBTRD REF=GR54DF,TAPE=TST

Related Macros