Info Catalog gawk: Updating ERRNO gawk: Extension API Description gawk: Accessing Parameters

gawk: Requesting Values

 
 16.4.8 Requesting Values
 ------------------------
 
 All of the functions that return values from 'gawk' work in the same
 way.  You pass in an 'awk_valtype_t' value to indicate what kind of
 value you expect.  If the actual value matches what you requested, the
 function returns true and fills in the 'awk_value_t' result.  Otherwise,
 the function returns false, and the 'val_type' member indicates the type
 of the actual value.  You may then print an error message or reissue the
 request for the actual value type, as appropriate.  This behavior is
 summarized in Table 16.1 table-value-types-returned.
 
                                      Type of Actual Value
 --------------------------------------------------------------------------
                         String   Strnum   Number   Regex   Array   Undefined
 -------------------------------------------------------------------------------
             String      String   String   String   String  false   false
             Strnum      false    Strnum   Strnum   false   false   false
             Number      Number   Number   Number   false   false   false
 Type        Regex       false    false    false    Regex   false   false
 Requested   Array       false    false    false    false   Array   false
             Scalar      Scalar   Scalar   Scalar   Scalar  false   false
             Undefined   String   Strnum   Number   Regex   Array   Undefined
             Value       false    false    false    false   false   false
             cookie
 
 Table 16.1: API value types returned
 

Info Catalog gawk: Updating ERRNO gawk: Extension API Description gawk: Accessing Parameters