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--- jvs:fscan:manual:chapter1:status [2011/03/31 14:49]
127.0.0.1 external edit
+++ jvs:fscan:manual:chapter1:status [2023/02/23 18:43] (current)
@@ Line 6: / Line 6: @@
 **usage: ?data**
-The '?' query operator can be used in place of the '$' data name identifier in any fScan command string. Whereas $dataname would be replaced in the command by the value of the variable DATANAME, ?dataname is replaced by either 1 or 0 depending on whether the variable DATANAME contains a valid data value or not.  A query on an undefined data variable would always return status 0.
+The '?' query operator can be used in place of the '$' data name identifier in any fScan command string.
+The value of a query is:\\
+-1 if the DATA name is not defined\\
+ if the DATA name is defined but empty (string data only)\\
+if the DATA name is defined and not an empty string.
+This is different than the '$' operator, which is replaced by the actual value of the named DATA.
 ==== The file found query -- ?exists ====

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