The following example shows a Pascal program that calls the
    C RTL using the DECC$CRTL_INIT function:

    $ PASCAL EXAMPLE1
    $ LINK EXAMPLE1
    $ TY EXAMPLE1.PAS
    PROGRAM TESTC(input, output);
    PROCEDURE DECC$CRTL_INIT; extern;
    BEGIN
       DECC$CRTL_INIT;
    END

    A shareable image need only call this function if it contains
    an VSI C function for signal handling, environment variables,
    I/O, exit handling, a default file protection mask, or if it is a
    child process that should inherit context.

    Although many of the initialization activities are performed only
    once, DECC$CRTL_INIT can safely be called multiple times.

    At least one frame in the current call stack must have that
    handler established for OpenVMS exceptions to get mapped to UNIX
    signals.