Xerox 6180N Using LCDS Print Description Language - Page 123

Specifying input parameters • If a block length is specified that is less than the minimum block length that is found on the tape, the system allocates input buffers, which are sized to the minimum tape block length. It is wise to specify the maximum block length in the JSL, so that input buffers are large enough to handle the largest block. However, specifying the maximum block length in the JSL may slow performance. If the actual tape block length is smaller than the JSL block length, no error message is reported; otherwise, an error is displayed. • The length on a 4 by 3 packed format tape is the number of 6bit bytes or characters in the tape block. BLOCK LMULT Specifies a multiplication factor that is applied to the contents of the block length field to determine the true block length. Syntax BLOCK LMULT = value Options Table 2-9. BLOCK LMULT parameter options and definitions Option value Definition An integer in the range of 1 to 15 that is multiplied by the value in the length field (refer to LENGTH parameter) to compute the number of bytes in the block. Default 1 BLOCK LTHFLD Specifies the length of the field that contains the block length. Syntax BLOCK LTHFLD = size Options Table 2-10. BLOCK LTHFLD parameter options and definitions Option size Definition An integer from 0 to 5 that specifies in bytes the length of the field that contains the block length. Using LCDS Print Description Language 2-15