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ZVERIF - check logical integrity of Zebra stores

CALL ZVERIF (IXDIV,IFLRTN,chTEXT)

with   IXDIV  1) the index of a single division to be verified;
              2) the index of the store to be verified;
                 = -1: all stores
                        (other negative values are reserved)

      IFLRTN  return flag, see below;

      chTEXT  identifying text to be printed if trouble.

This routine has two somewhat different modes of operation:

Normally ZVERIF checks all the data in and relevant to a complete store, or even several stores. It goes to ZFATAL if it finds trouble.

But if verification is for one single division only, only the banks of this division are checked and control is given back to the caller if the flag IFLRTN is non-zero, in which case the number of normally fatal conditions is delivered in IQUEST(1). This is intended to be used if one receives a data-structure in memory (with FZIN, say) which may be bad. Rather than letting the program run to crash one can realize the situation and wipe the division. This must be done with MZWIPE because this is the only way to get rid of the data without Zebra looking at them.

This routine inspects all link areas and all banks in the stores selected, performing the following checks:

    (0)  process and store control tables intact;
    (1)  bank chaining intact;
    (2)  a non-zero structural link must point to a true bank address;
    (3)  consistency of "up" and "origin" links;
    (4)  a link in a bank in division A pointing to division B
         is checked for consistency with the cross-reference matrix;
    (5)  a non-zero reference link in a bank must not point
         into a reserve area;

ZVERIF is used by the automatic verification procedure ZVAUTO, see next section.


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