Radio Shack TRS-80 Model II Reference Manual page 112

Model II TRSDOS
VERIFY
There are two syntaxes for this command:
A. VERIFY {switch}
B. VERIFY {DETECT
=
sWitch}
switch is either
ON
or
OFF.
In syntax form A, switch tells
TRSDOS
whether to verify all diskette
writes (read after each write).
TRSDOS
starts with this switch
ON.
If
omitted, the current status is given.
In syntax form B, switch controls the diskette
ID
sensing feature. If
DETECT
=
ON,
then
TRSDOS
will automatically check the diskette
ID
before any diskette access.
TRSDOS
starts with the
DETECT
switch
ON.
If
DETECT
=
OFF,
then
TRSDOS
will not automatically check the
diskette
ID
before each diskette read. In this case, you must use the
"I" command immediately after swapping diskettes.
This command controls the verify function. When it is on,
TRSDOS
will read
after each write operation, to verify that the data is readable. If the data is not
readable, after retries,
TRSDOS
will return an error message, so you'll know
that the operation was not successful.
Note:
TRSDOS
always verifies directory writes. User writes (writing data into a
file) are only verified when
VERIFY
is
ON.
TRSDOS
starts up with
VERIFY ON.
For most applications, you should leave it
ON.
While
DETECT = ON:
If the operator swaps diskettes while a file is open,
TRSDOS
will abort any attempted
110
to that file with error
7.
When the correct diskette is
reinserted,
TRSDOS
will be able to perform the desired
110
operation.
When improper swapping is a possibility, programmers should write error-7
recovery procedures which prompt the operator to insert the correct diskette.
Examples
VEHIFY 01\1
Turns on the verity function.
VEFHFY OFF
Turns off the verify function.
VEHIFY
Displays the status of the verify switch.
VERIFY DETECT
=
OFF
Turns off the diskette swap detection feature for reads only.
148