Pragma Export_Procedure

Syntax:

     pragma Export_Procedure (
          [Internal        =>] LOCAL_NAME
       [, [External        =>] EXTERNAL_SYMBOL]
       [, [Parameter_Types =>] PARAMETER_TYPES]
       [, [Mechanism       =>] MECHANISM]);
     
     EXTERNAL_SYMBOL ::=
       IDENTIFIER
     | static_string_EXPRESSION
     | ""
     
     PARAMETER_TYPES ::=
       null
     | TYPE_DESIGNATOR {, TYPE_DESIGNATOR}
     
     TYPE_DESIGNATOR ::=
       subtype_NAME
     | subtype_Name ' Access
     
     MECHANISM ::=
       MECHANISM_NAME
     | (MECHANISM_ASSOCIATION {, MECHANISM_ASSOCIATION})
     
     MECHANISM_ASSOCIATION ::=
       [formal_parameter_NAME =>] MECHANISM_NAME
     
     MECHANISM_NAME ::=
       Value
     | Reference
     | Descriptor [([Class =>] CLASS_NAME)]
     | Short_Descriptor [([Class =>] CLASS_NAME)]
     
     CLASS_NAME ::= ubs | ubsb | uba | s | sb | a

This pragma is identical to Export_Function except that it applies to a procedure rather than a function and the parameters Result_Type and Result_Mechanism are not permitted. GNAT does not require a separate pragma Export, but if none is present, Convention Ada is assumed, which is usually not what is wanted, so it is usually appropriate to use this pragma in conjunction with a Export or Convention pragma that specifies the desired foreign convention.

Passing by descriptor is supported only on the OpenVMS ports of GNAT. The default behavior for Export_Procedure is to accept either 64bit or 32bit descriptors unless short_descriptor is specified, then only 32bit descriptors are accepted.

Special treatment is given if the EXTERNAL is an explicit null string or a static string expressions that evaluates to the null string. In this case, no external name is generated. This form still allows the specification of parameter mechanisms.