http://stackoverflow.com/questions/21076046/

gistfile1.c

int read_file (char *filename)
{
	FILE *fin;

	if ( !(fin = fopen(filename, "r")) )
		return -1;

	/* ... */

	return fclose(fin);
}

int main ()
{
	char filename[100];

	if ( read_file(filename) )
	{
    	perror("file.dat");
    	exit(1);
	}

	return 0;
}