If the disk you want to access replaces an OS disk, message DMSACC724I appears at your terminal.
If you specified any options or fileid in theACCESS command to an OS disk, a warning message, DMSACC230W, appears to notify you that such
options or fileid were ignored.DMSACC returns to the calling routine
with a warning code of 4.DMSACF verifies that the disk you want to access is an OS disk and, if it is, exits immediately. DMSACM MODULE: DMSACM saves the disk label and VTOC address in the ADT block- Ii-the disk is an as disk. DMSACM checks to determine if a
previous access to an os disk leadedDMSROS. If not, DMSACM calls DMSSTT to verify that DMSROS text exists. Upon successful return from
STATE,DMSACM loads DMSROS text into the high storage area with the same
protect key and calls theOS access routine (ROSACC) of DMSROS to read
the format 4DSCB of the disk. Upon successful return from DMSROS, control returns to the calling routine. Any other errors are treated as
general logen errors.DMSALU MODULE: If the disk is an os disk, DMSFRET returns the as FST blocks clf-any) to free storage. DMSALU clears the OS FST pointer in
all active as file control blocks, decrements theDMSROS usage count
and, if the usage count is zero, clears the address ofDMSROS in the
nucleus area.DMSALU also calls DMSFRET to returns to free storage the
area whichDMSROS occupies. DMSARE MODULE: DMSARE ensures that the disk you want to relase is an OS aisk:- -DMSliE calls DMSALU to release alIOS FST blocks and, if
necessary, to free theDMSROS occupies. UFon return from DMSALU, DMSARE clears the common CMS and OS active disk table. • DSN If you specify the parameter DSN as a question mark (1) ,
FILEDEF displays the messageDMSFLD220R to request you to type in an OS data set name with the format Q1.Q2.QN. Ql, Q2, and QN are the
qualifiers of anOS data set name. If you specify the parameter DSN as Ql.Q2.QN, FILEDEF assumes that Ql, Q2, and QN are the qualifiers
of anOS data set name, and stores the qualifiers with the format Ql.Q2.QN in a free storage block and chains the block to the FCB. • CONCAT -- If you specify the CONCAT option, FILEDEF assumes that the
specified FILEDEF is unique unless a filedef is outstanding with a
matchingddna.e, filename, and filetype. This allows you to specify
more than one FILEDEF for a particular ddna.e. TheCONCAT option
also sets theFCBCATML bit in the FCB to allow the OS simulation
routine to know theFCB is for a concatenated MACLI8. • MEMBER -- If you specify the member option, filedef stores the member
name inFCBMEMBR in the FCB to indicate that the OS simulation
routine should set the read/write pointer to point to the specifiedBPAM file member when OPEN occurs. DMSLDS saves the return register, sets itself with the
nucleus protection key, clears the dsname key, and initializes its
internal flag.DMSLDS verifies parameter list validity. The data set name must not
exceed 44 characters, and thedisk mode (the last parameter before the
options) must be valid.DMSLDS joins the quailifiers with dots (.) to
form valid data set names. If you specify the data set name as a
question mark (?),DMSLDS prompts you to enter the dsname in exactly the
same form as the dsname which apFears on the disk.
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If you specified any options or fileid in the
options or fileid were ignored.
with a warning code of 4.
previous access to an os disk leaded
STATE,
protect key and calls the
the format 4
general logen errors.
all active as file control blocks, decrements the
and, if the usage count is zero, clears the address of
nucleus area.
area which
necessary, to free the
FILEDEF displays the message
qualifiers of an
of an
specified FILEDEF is unique unless a filedef is outstanding with a
matching
more than one FILEDEF for a particular ddna.e. The
also sets the
routine to know the
name in
routine should set the read/write pointer to point to the specified
nucleus protection key, clears the dsname key, and initializes its
internal flag.
exceed 44 characters, and the
options) must be valid.
form valid data set names. If you specify the data set name as a
question mark (?),
same form as the dsname which apFears on the disk.
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