address is the starting address of the CSECT. The address must be
two, four, or six hexadecimal digits. For example, for a CSECT starting at location 400, you would specify the BASE 0400 in the BASE control record. If a subsequent VER card
requests verification of location 0408, the BASE of 0400 is
subtracted from and the program verifies location 08 in
the CSECT. This example applies if you specify TITLIB, LOADLIB, or MODULE and the module map is present. However, if
ne module map is present for a ftODULE file (that is, the
module was generated with the IOftAP option), then all
operations are performed as if the BASE address is location O. For example, if you specify a BASE of 400 and the address you wish to inspect or modify is 408, then you must specify 08 and
not 408 in REP and VER control records. The address in this
case is from the start of the module. If you do not specify
csectname in the HAME control record. vou cannot specify anY BASE value other than 00. The BASE control record is optional. See the discussion under "VER or VERIFY Contrel
Record." If specified, the BASE control record must follcw
the BAftE record, but it need not follow the lAME record immediately. For example, you could have the following
sequence of control records: NAftE, VER, REP, BASE, VER, REP. The VER control record requests verification of instructions or data
within a CSECT. If the verification fails, the Frogram does not perform
a subsequent REP operation until it encounters another IAftE control
record.
The VER control record is optional. ftore than one VER record can
follow a single lAME record.
The format of the VER control record is: {
VERIFY
} VER disp data disp is the hexadecimal displacement of the data to be inspected
from the start of the CSECT, if you did not submit a BASE control record for this CSECT. If you did submit a BASE control record, then disp is the actual location of the data.
The disp must be tvo, four, or six hexadeci.al digits. This displacement does not have to be aligned on a full word
boundary. If this displacement value is outside the limits of
the CSECT specified by the preceding IAftE control record, the VERIFY control record is rejected.
data is the data against which the data in the CSECT is to be compared. This must be an even number of hexadecimal digits. Por example, if the location you wish to verify is 3CC, and
the CSECT begins at location 2BO, you can either issue: 204 VM/370 OFerator's Guide
BASE 02BO YER 03CC data
or you can omit the BASE control record, subtract the CSECT start address from the address of the data, and issue: YER 011C data
This also applies to the disp operand of the REP control
record.
Note: If the YER control statement references a TITLIB file that contains ORG statements causing more than one occurrence
of an address, only the first occurrence is tested when the
displacement on the VER statement references the ORG statement
addresses.
The REP control record .odifies instructions or data at the specified
location within the CSECT that you specified in a preceding Il!E control
record. The data specified in the REP control record replaces the data
at the CSECT location specified by the disp operand. This replacement is on a "one-for-one" basis; that is, one byte of data defined in the
control record replaces one byte of data at the location that you specified. If the reFlacement fails, the program does not perform additional REP operations until it encounters another BAftB control
record. The REP control record is oFtional. !ore than one REP record can
follow a single NAME record.
The format of the REP control record is:
REP disp data
disp is the hexadecimal displacement of the data to be replaced
from the start of the CSECT, if you did not submit a B1SE control record for this CSBCT. If you did submit a B1SE control record, then disp is the actual location of the data.
The disp .ust be two, four, or six hexadecimal digits. This
displacement need not address a fullvord boundary. If this
displacement value is outside the limits of the CSECT being
modified, the program does not perform the replacement
operation.
data is the data that is to replace the data in the CSECT. This must be an even number of hexadecimal digits. !Qte: Although you do not have to
data, you should do so to make sure you expect it to be.
verify a location before replacing
that the data being changed is what Section 4. Vft/370 Service Programs 205
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