This syntax is used for string-valued attributes where upper and lower case are considered unequal for comparisons (e.g. "DUNDEE" and "Dundee" do not match). It corresponds to the X.500 string syntaxes called Printable-String-Syntax and Case-Ignore-String-Syntax.
The DS will accept any contents for a Printable-string; it will not attempt to verify that they are indeed printable. Individual attribute types may associate a minimum and maximum size with any string, and those size limits are enforced; any value outside the legal size range will not be accepted.
OM SYNTAX: String (Printable)
MATCHES FOR EQUALITY SUBSTRINGS
::= { ms-AttributeSyntax 3 }
Where a syntax is defined here as a PrintableString, it is implemented by the Touchdown Directory Service as an SBCS/DBCS text string (which may have a code page number associated with it). When a string is stored, the client's main code page number is stored with it.
Note that X.208 defines the PrintableString data type as using only the set of characters listed in Table 5/X.208:
A..Z
a..z
0..9
space
' ( ) + , - . / : = ?
Thus when the DS exchanges data with non-Touchdown DS's, some strings may not be translatable to the foreign DS. In another deviation from X.500, the Touchdown DS does not attempt to remove or compress multiple blanks supplied in string values. Thus "a b" and "a b" will be stored differently and will not match for equality.