If the CMSCB fcbmembr field contains a member name (filled in by FILEDEF
with themember option), DMSSOP issues an OS FIND macro to position the
file pointer to the correct member. If an error occurs on the call to
the FIND macro, error messageDMSSOP036E appears and DMSSOP does not
open theDCB. • BSP (backspace) Routine -- Upon entry, backspace checks for the FCB OS bit. If it is on, the BSP routine calls DMSROS (ROSNTPTB) to
backspace the TTR and control returns to the calling routine.• FIND (type_D) Routine -- Upon entry to find, the find routine checks
the FCBOS bit. If it is on, the FIND routine takes the as FST address from the CMSCB or, if the CONCAT bit is on, from the global MlCLIB list. The FIND routine then calls (ROSFIND) to find
the member name and TTR.DMSROS searches for a matching me.ber name or, if the FCBMVPDS option is specified, a higher member na.e. If the returu code G OL 0, uL If the iCBCAThL is not on,
control returns to the calling routine with the return code fro.DMSROS. If the return code is 4 and the FCBCATeL bit is on, DeSSVT checks to determine if all the global M!CLIBS were searched. If they
were, control returns to the calling routine with theDMSROS return
code. If they were not,DMSSVT issues the FIND on the next MACLIB in
the global list.• BLDL Routine--BLDL list = FF LL NAME TTR KZC DATA • If the DCB refers to an as disk, the BLDL routine fills in the TTR, C-byte and data field from the os data set. SEARCH Routine --The search
currently active is included
currently accessible.
routine
in the
ensures that any as
search order of all
disk
disks• DISK Routine --The disk routine displays the status of any or alIOS disks using the following fora: 'MODE(CUU): (NO. CILS.), TIPE RIO - OS.' DMSSTT MODULE -- DMSSTT verifies that the disk being searched is an OS dIsk:- nMSSTT calls DMSLFS to get the FST associated with the data set. Upon return from DMSLFS, DMSSTT checks the return code to ensure that CMS supports the data set attributes. A return code of 81 or 82
indicates thatCMS does not support the data set and message DftSSTT229E occurs to that effect. DftSSTT then clears the FST copy with binary
zeros, and moves thefilename, filetype, file.ode, BLKSIZE, LRECL, RECFM, and flag byte to the FST copy. From this point on, co.mon code
execution occurs for bothCMS and os disks. • CHRCNVRT Routine --The CHRNCVRT routine converts a CCHH address to a
relative track address.
2-136IBM VM/370 System Logic and Program Determination--Volume 2
with the
file pointer to the correct member. If an error occurs on the call to
the FIND macro, error message
open the
backspace the TTR and control returns to the calling routine.
the FCB
the member name and TTR.
control returns to the calling routine with the return code fro.
were, control returns to the calling routine with the
code. If they were not,
the global list.
currently active is included
currently accessible.
routine
in the
ensures that any as
search order of all
disk
disks
indicates that
zeros, and moves the
execution occurs for both
relative track address.
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