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  Syntax:   label PROC [distance] [langtype] [visibility]
            [<prologuearg>]
            [USES reglist] [,parameter [:tag]]...
                    [LOCAL varlist]
                    statements
            label ENDP
 
  See also: Procedure Diagram, USES, INVOKE, PROTO, LOCAL, RET,
            .MODEL, OPTION PROLOGUE, OPTION PROC,
            Using VARARG in Procedures, MASM 5.1 Compatibility
 
  Description:
 
     Defines a procedure called <label>. To use <parameter>, you must
     have previously specified a language type or used the <langtype>
     parameter. You should use a PROTO prototype before each procedure
     defined with the PROC directive. This ensures proper type checking
     and allows you to call the procedure with the INVOKE directive.
 
     Procedures usually end with the RET instruction. You can remove
     data from the stack by specifying the number of bytes as a
     parameter of the RET instruction.
 
     The assembler automatically generates PROLOGUE and EPILOGUE code
     to pass stack arguments properly to the procedure and clean up the
     stack after completion of the procedure. You can override the
     default prologue and epilogue code with user-defined macros by
     using the OPTION PROLOGUE: and OPTION EPILOGUE: directives.
     The RETF or IRETF instructions do not cause the assembler to
     generate epilogue code.
 
     Procedures can be nested if they do not have parameters, local
     variables or the USES parameter and do not generate a new segment
     or group. You can avoid having to nest procedures by using the RETN
     and RETF instructions.
 
     Local variables must be declared (using the LOCAL directive)
     before any instructions. There can be several LOCAL statements in
     a procedure.
     See: ◄LOCAL directive►
 
     Parameter      Description
 
     label          Defines name for the procedure. Follows naming
                    convention of <langtype>.
 
     prologuearg    Arguments to pass to the prologue procedure. With
                    the default PROLOGUE and EPILOGUE, the FORCEFRAME
                    argument generates a stack segment, even if one is
                    not necessary. LOADDS causes the DS register to be
                    saved in the PROLOGUE and restored in the EPILOGUE.
                    Parameters must be separated by commas. Angle brackets
                    are required but not passed.
 
     distance       NEAR, FAR, NEAR16, NEAR32, FAR16, or FAR32. Indicates
                    the call distance of this procedure. If you choose
                    NEAR or FAR, the assembler will select 16- or 32-bit
                    NEAR or FAR depending on the current segment size. If
                    you do not specify this option, the assembler
                    determines the distance from the memory model and
                    processor type. NEAR is the default if you do not use
                    the .MODEL directive.
 
     langtype       Any valid language type. Determines naming style
                    and calling convention.
                    See: ◄language type►
 
     visibility     PRIVATE, PUBLIC, or EXPORT. Determines how the
                    procedure is made available to other modules. PUBLIC
                    is the standard default, but the default can be reset
                    with the OPTION PROC directive. EXPORT implies PUBLIC
                    and FAR and informs the linker that the procedure
                    should be placed in the export entry table.
 
     reglist        List of registers that the prologue preserves on the
                    stack and the epilogue restores on exit. Separate
                    multiple registers with spaces.
 
     parameter      Procedure parameter. The assembler translates
                    argument references into a direct reference to the
                    stack location. Separate multiple arguments with
                    commas.
 
     tag            Either a qualified type or VARARG. VARARG allows a
                    variable number of arguments to be passed as a
                    comma separated list to <argument>. If VARARG is
                    used, it must be applied to the last parameter of
                    the PROC directive. VARARG is only allowed with
                    the C, SYSCALL, and STDCALL language types. If <tag>
                    is omitted, the assembler defaults to WORD in a 16-bit
                    segment or DWORD in a 32-bit segment.
                    See: ◄qualified type►, ◄VARARG►
 
     statements     Assembly-language statements and directives.
                                    -♦-