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RZ link area

A permanent reference link area, RZCL, is automatically created upon the first call to RZFILE or RZMAKE. This link area is defined in the patchy sequence P=QCDE,D=QCDE,Z=RCL. This link area contains the following definitions:

LTOP: Address of control bank for current RZ file
LRZ0: Address of bank for memory files
LCDIR: Address of directory structure for current working directory
LRIN: Last record read
LROUT: Last record written
LFREE: Pointer to list of free records
LUSED: Pointer to list of used records
LPURG: Pointer to list of purged records
LTEMP
LCORD: Pointer to list of ordered cycles
LFROM: Pointer to copied directory

LQRS (system link 7) points to a linear chain containing the control banks for all RZ files currently open. A bank for a specific Fortran logical unit or C file pointer can be located using the following code. (The numeric bank identifier is set to the Fortran logical unit or C file pointer).

Locating the RZ control bank by logical unit

*
*     Any RZ files open?
*
      IF(LQRS.EQ.0)GO TO 99
*
*     Yes, loop over linear chain looking for the bank
*     for logical unit LUN
*
      LRZ=LQRS
  10  IF(LRZ.EQ.0)GO TO 99
      IF(IQ(KQSP+LRZ-5).NE.LUN)THEN
         LRZ=LQ(KQSP+LRZ)
         GO TO 10
      ENDIF
*
*     LRZ now points to the control bank for LUN
*     LRECL is equal to # of data words of bank
*
      LRECL = IQ(KQSP+LRZ-1)
*
...
  99  CONTINUE

Janne Saarela
Mon May 15 08:34:47 METDST 1995