#include <IO.h>
int *to_contigs_only(
int num_contigs,
contig_list_t *cl);
This functions converts an array of contig_list_t structures to an array
of integers containing only the contig number information. The cl and
num_contigs elements correspond to the returned rargv and
rargc arguments from the lget_contig_num function.
It returns a malloc array of integers for success or NULL for failure.