getopt_long_only - parse long command-line options

#define _GNU_SOURCE
#include <getopt.h>
int getopt_long_only(int argc, char *argv[],
 const char *optstring,
 const struct option *longopts, int *longindex);

getopt_long_only() is like getopt_long(3), but '-' as well as "--" can indicate a long option. If an option that starts with '-' (not "--") doesn't match a long option, but does match a short option, it is parsed as a short option instead.

getopt(1), getopt(3), getopt_long(3), getsubopt(3)