Example using an external td symbol

Example of using an external TD symbol

1. 
   /* This C module named td3.c   */
   long   t_data;
   extern  void mod_s();
   main()
   {
           t_data = 234;
            mod_s();
            printf("t_data is %d\n", t_data);
   }
   

2. The following is the assembler source for module mod3.s:

   
           .file "mod3.s"
           .csect .mod_s[PR]
           .globl .mod_s[PR]
           .set    RTOC, 2
           l   5, t_data[TD](RTOC)  # Now GPR5 contains the
                                    # t_data value
           ai  5,5,14
           stu 5, t_data[TD](RTOC)
           br
           .toc
           .extern  t_data[TD]  # t_data is a external symbol
   

3. The following commands assemble and compile the source programs into an executable td3:

   
   ./as -o mod3.o mod3.s
   cc -o td3 td3.c mod3.o
   

4. Running td3 prints the following:

   
   t_data is 248