BLANK

 Indicates how blanks are interpreted in a file.  It takes the
 following form:

 BLANK = blnk

 blnk  Is a character expression with one of the following 
       values:

 'NULL'  Ignore all blanks in a numeric field (unless the field 
         is all blanks, in which case treat blanks as zero).
 'ZERO'  Treat all blanks other than leading blanks as zeros.

 The default is 'NULL' (for explicitly OPENed files, preconnected
 files, and internal files).

 If the BN or BZ edit descriptors are specified for a formatted
 input statement, they supersede the default interpretation of
 blanks.