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**C**

**PASCAL**

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The **C **and** PASCAL **attributes of a PROCEDURE prototype specifies that parameters are always passed on the stack. In 32-bit programs, both C and PASCAL conventions pass the parameters to the stack from right to left. The difference is in who (callee(C) or caller(PASCAL)) is cleaning the stack on return. Also, in C/C++ there is a difference in mangling of the external name, but in Clarion, name mangling is the same for both C and PASCAL. PASCAL is also completely compatible with the Windows API calling convention for 32-bit compiled applications--it is the Windows-standard calling convention (and also disables name mangling).

These calling conventions provide compatibility with third-party libraries written in other languages (if they were not compiled with a TopSpeed compiler). If you do not specify a calling convention in the prototype, the default calling convention is the internal, register-based parameter passing convention used by all the TopSpeed compilers.

**Example:**

** MAP**

**  MODULE('Party3.Obj')                            !A third-party library**

**Func46 PROCEDURE(*CSTRING,*REAL),REAL,C,RAW       !Pass REAL then CSTRING, address-only **

**Func49 PROCEDURE(*CSTRING,*REAL),REAL,PASCAL,RAW  !Pass CSTRING then REAL, address-only **

**  END**

** END**

**See Also:**

[[procedure prototypes.htm|PROCEDURE Prototypes]]

__Prototype Parameter Lists__