1. simplified (custom) init sequence

This method is useful for the simplest, gui-only applications that
potentially do not have plugins.

int main(int argc, char *argv[])
{
	pcb_fix_locale_and_env();

	/* set up non-hidlib related app states */
	...

	pcb_hidlib_init1(conf_core_init);

	/* process command line args */
	...

	pcb_hidlib_init2(pup_buildins);

	/* set up hidlib related app states - all main infrastructure is up by now */
	...

	/* initialize the gui and run the main loop */
	pcb_gui = pcb_hid_find_gui(gui_name);
	if (pcb_gui == NULL) {
		pcb_message(PCB_MSG_ERROR, "can't find HID '%s'\n", gui_name);
		pcbhl_log_print_uninit_errs("");
		exit(1);
	}
	if (pcb_gui->parse_arguments(&argc, &argv) != 0) {
		pcb_message(PCB_MSG_ERROR, "can't init HID '%s'\n", gui_name);
		pcbhl_log_print_uninit_errs("");
		exit(1);
	}
	pcb_gui->do_export(&camv.hidlib, 0);

	/* application state uninit */
	...
}


2. standard init sequence

Hidlib calls help to initialize the plugin system, parse the command line
argument, choose command line action, exporter or GUI in a standard way.
Full featured hidlib applications with feature and export plugins should
use this sequence.

static const char *camv_action_args[] = {
/*short, -long, action, help, hint-on-error */
	"V",  "-version",         "PrintVersion()",     "Print version info and exit",                             NULL,
	"V",  "-dump-version",    "DumpVersion()",      "Print version info in script readable format and exit",   NULL,
	NULL, "-copyright",       "PrintCopyright()",   "Print copyright and exit",                                NULL,
	NULL, NULL, NULL, NULL, NULL /* terminator */
};

int main(int argc, char *argv[])
{
	pcbhl_main_args_t ga;

	pcb_fix_locale_and_env();

	pcbhl_main_args_init(&ga, argc, camv_action_args);

	pcb_hidlib_init1(conf_core_init);
	for(n = 1; n < argc; n++) {
		/* process application-specific arguments here and skip the next line for those */
		n += pcbhl_main_args_add(&ga, argv[n], argv[n+1]);
	}
	pcb_hidlib_init2(pup_buildins);

	/* direct exporting via -x */
	if (pcbhl_main_args_setup1(&ga) != 0) {
		camv_main_uninit();
		pcbhl_main_args_uninit(&ga);
		exit(1);
	}

/* Initialize actions only when the gui is already known so only the right
   one is registered (there can be only one GUI). */
#include "generated_lists.h"

	if (pcbhl_main_args_setup2(&ga, &n) != 0) {
		camv_main_uninit();
		pcbhl_main_args_uninit(&ga);
		exit(n);
	}

	if (ga.hid_argc > 0) {
		/* command line leftover: typically file name(s) to load, in
		   ga.hid_argv[0 .. ga.hid_argc-1]; */
	}

	/* do the export if -x was specified */
	if (pcbhl_main_exported(&ga, ...)) {
		camv_main_uninit();
		pcbhl_main_args_uninit(&ga);
		exit(0);
	}

	/* main loop */
	do {
		/* optional: if a plugin is required for basic GUI operation, load it here */
		if (PCB_HAVE_GUI_ATTR_DLG)
			gui_support_plugins(1);
		pcbhl_mainloop_interactive(&ga, ...);
	} while(pcb_gui != NULL);

	/* application specific uninit */
	...

	pcbhl_main_args_uninit(&ga);
	return 0;
}