Kenwood HP 9000 manual Dynprog.c Example Dynamic Link and Load Program

Linker Tasks

Using Linker commands

Note that the line CFLAGS =… causes any C files to be compiled in ANSI mode (-Aa) and causes the compiler to search for routines that are defined in the Posix standard (-D_POSIX_SOURCE).

For details on using make refer to make(1).

Source for dynprog. Here is the source file for the dynprog program.

dynprog.c — Example Dynamic Link and Load Program

#include <stdio.h> #include <nlist.h>

extern void * alloc_load_space(const char * base_prog, const char * obj_files, const char * dest_file);

extern void * dyn_load(const char * base_prog,

unsigned int			addr,
const char *			obj_files,
const	char	*	dest_file,
const	char	*	entry_pt);

const char * base_prog = “dynprog”;			/* this executable’s name
*/
const char * obj_files = “file1.o file2.o”; /* .o files to combine
*/
const char * dest_file = “dynobj.o”;			/* .o file to load
*/
const char * entry_pt		= “foo”;	/* define entry pt name
*/
void glorp (const char *); /* prototype for local
function	*/
void (* foo_ptr) ();		/* pointer to entry point foo
*/
void (* bar_ptr) ();		/* pointer to function bar
*/
int * counter_ptr;		/* pointer to variable counter [file2.c]
*/
main()
{
unsigned int addr;		/* address at which to load dynobj.o		*/
struct nlist nl[3];		/* nlist struct to retrieve addresse		*/

/*

STEP 1: Allocate space for module: */

addr = (unsigned int) alloc_load_space(base_prog, obj_files, dest_file);

/*

STEP 2: Load the file at the address, and get address of entry point:

*/

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