/*
 *  callsym.c - zavola symbol z knihovny.
 *
 *  This is an example file for the UNIX - Programming and System
 *  Administration II course.
 *
 *  Copyright (C) 2001  Jan "Yenya" Kasprzak <kas@fi.muni.cz>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
#include <dlfcn.h>
#include <stdio.h>

typedef void (*handler)(void);

int main(int argc, char **argv)
{
	void *library, *symbol;

	if (argc != 3) {
		fprintf(stderr, "Usage: %s [libary] [funcion]\n", *argv);
		return 1;
	}

	if (!(library = dlopen(argv[1], RTLD_NOW))) {
		fprintf(stderr, "dlopen(%s): %s\n", argv[1], dlerror());
		return 2;
	}

	if (!(symbol = dlsym(library, argv[2]))) {
		fprintf(stderr, "dlsym(%s): %s\n", argv[2], dlerror());
		return 3;
	}

	printf("Calling symbol %s at %p\n", argv[2], symbol);
	((void (*)(void))symbol)();

	return 0;
}