External linkage attribute for public data located in DLL's

Extern Import symbolname[( subscripts)] [ alias "aliasname"] [ as DataType] [, ...]

Is used only (with the Extern keyword) in external modules to access global variables from Win32 DLLs: the variable names will be added to the dynamic library import list so that their addresses can be fixed at run-time.
This is due to the level of indirection on any such access: an implicit pointer dereference.

/* mydll.c :
    compile with
      gcc -shared -Wl,--strip-all -o mydll.dll mydll.c

__declspec( dllexport ) int MyDll_Data = 0x1234;

/'  import.bas :
    Compile With
      fbc Import.bas
#inclib "mydll"

Extern Import MyDll_Data Alias "MyDll_Data" As Integer

Print "&h" + Hex( MyDll_Data )

' Output:
' &h1234

Dialect Differences:
Differences from QB:
See also:
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