$ListCmp

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Compare two $lists and produce $list describing differences

Note: Many $functions have been deprecated in favor of Object Oriented methods. The OO equivalent for the $ListCmp function is the Compare function.

This function compares two $lists and produces a $list describing the differences between the $lists.

The $ListCmp function accepts five arguments and returns a numeric result. It is a callable $function.

The first argument is the identifier of a $list containing data with 8 byte sequence numbers. This is a required argument.

The second argument is the identifier of a $list containing data without 8 byte sequence numbers. This is a required argument.

The third argument is the identifier of the output $list. This is a required argument.

The fourth argument is a number indicating a synchronization count. When the two input $lists are being compared and a difference has been found, this count indicates the number of lines that must match before they are treated as a true match. This is an optional argument and defaults to 1.

The fifth argument is a pad character to be used to pad any input line that is too short. This is an optional argument and defaults to blank.

Syntax

[%RESULT =] $ListCmp(list_id1, list_id2, list_id3, sync_count, pad)

%result is set either to the number of items in the output $list, or to a negative error code if an error has occurred.

Error codes

-3 - No room to create $list items (if LISTFC $SirParm parameter not set) -5 - Required argument not specified -6 - $List identifier invalid -7 - Invalid synchronization count -8 - Input $list 1 has invalid format

Usage notes

  • The output $list produced by $ListCmp is in a format that is suitable as input to $ListUpd. For example, if input $list 1 contains:

    00010000B 00020000 00030000PRINT 'QUENTIN COMPSON' 00040000 00050000END

    and input $list 2 contains:

    B PRINT 'QUENTIN COMPSON' PRINT 'HARVARD DIVING TEAM, 1908' END

    Then this statement:

    %RESULT = $ListCmp(%INLIST1, %INLIST2, %OUTLIST)

    results in the $list identified by %OUTLIST containing:

    ./ I 00030000 $ 00030001 00010000 PRINT 'HARVARD DIVING TEAM, 1908'

    The first input $list to $ListCmp can be most easily created with the $ProcDat function using the third $ProcDat parameter to indicate a sequence number.

Products authorizing $ListCmp