Compiling and Linking

After writing a user-defined program, use the rtlink shell script to link it with the necessary TIBCO SmartSockets libraries. These sections present some examples of using the rtlink script to link the program stored in the myprog.c and extfunc.c files.

On UNIX

Here are examples of two methods of invoking the rtlink script on UNIX. In one example, the compiling and linking steps are executed separately; in the other, they are combined into one step. Both examples use the -o flag to explicitly name the executable, and the -O flag to enable compiler and SmartSockets optimization. By default, rtlink uses the cc command to compile and link, but you can override this by using the CC environment variable. For more information on compiling and linking, see the section on rtlink in TIBCO SmartSockets Utilities.

/* Separate compiles followed by a separate link */ 
$ cc -O -I$RTHOME/include/$RTARCH -c myprog.c 
$ cc -O -I$RTHOME/include/$RTARCH -c extfunc.c 
$ rtlink -O myprog.o extfunc.o -o myprog.x 
 
/* Combined compiles and link */ 
$ rtlink -O myprog.c extfunc.c -o myprog.x 

Using a Different Compiler

By default, rtlink uses the cc command to compile and link files. If the CC environment variable is set, rtlink instead uses the CC environment variable to determine the command to invoke. To use a different compiler, set this environment variable to the compiler you wish to use. Here is an example using a C++ compiler:

$ env CC=g++ rtlink -O myprog.C extfunc.C -o myprog.x 

Never set CC to rtlink. This causes recursion, as rtlink calls itself over and over.

Using Make

If you are using the make utility to control and execute your compilations, you can instead set the CC variable in your makefile and make will automatically set the CC environment variable each time it runs a command. Here is an example of setting CC from a makefile to use the GNU C compiler:

CC = gcc 
CFLAGS = -O -I$(RTHOME)/include/$(RTARCH) 
OBJECTS = myprog.o extfunc.o 
 
myprog.x: $(OBJECTS) 
    rtlink $(OBJECTS) -o $@ 

If you are using GNU make, this may be needed instead in your makefile or GNUmakefile:

export CC = gcc 
CFLAGS = -O -I$(RTHOME)/include/$(RTARCH) 
OBJECTS = myprog.o extfunc.o 
 
myprog.x: $(OBJECTS) 
    rtlink $(OBJECTS) -o $@ 

On OpenVMS

On OpenVMS, the rtlink syntax is similar to that for UNIX, except that it is not possible to combine the compilation and link steps. These steps must be explicitly invoked. This example uses the /executable qualifier to explicitly name the executable. For more information on compiling and linking, see the section on rtlink in TIBCO SmartSockets Utilities.

/* Separate compiles followed by a separate link */ 
$ cc/optimize myprog.c 
$ cc/optimize extfunc.c 
$ rtlink/executable=myprog.exe myprog.obj extfunc.obj 

The compilations create object files named myprog.obj and extfunc.obj. rtlink creates an executable named myprog.exe.

On Windows

On Windows, compiling and linking is usually done in the Visual C++ Developer Studio environment. There is no rtlink script on Windows. You can use one of several example Visual C++ makefiles in %RTHOME%\examples\smrtsock\manual as a starting point for your application executables.

Under Windows, if you are using SmartSockets for the first time, you need to set the paths for your include files and libraries in Developer Studio. You must also set the Project settings in Developer Studio. See the TIBCO SmartSockets Installation Guide for details on this.