ex29.c

#include <stdio.h>
#include "dbg.h"
#include <dlfcn.h>

typedef int (*lib_function) (const char *data);

int main(int argc, char *argv[])
{
	int rc = 0;
	check(argc == 4, "USAGE: ex29 libex29.so function data");

	char *lib_file = argv[1];
	char *func_to_run = argv[2];
	char *data = argv[3];

	void *lib = dlopen(lib_file, RTLD_NOW);
	check(lib != NULL, "Failed to open the library %s: %s", lib_file,
		dlerror());

	lib_function func = dlsym(lib, func_to_run);
	check(func != NULL,
		"Did not find %s function in the library %s: %s", func_to_run,
		lib_file, dlerror());

	rc = func(data);
	check(rc == 0, "Function %s return %d for data: %s", func_to_run,
		rc, data);

	rc = dlclose(lib);
	check(rc == 0, "Failed to close %s", lib_file);

	return 0;

error:
	return 1;
}