getservbyname programming

The getservbyname() function returns a servent structure for the entry from the database that  matches  the  service name  using protocol proto.  If proto is NULL, any protocol will be matched.  A connection is opened to the database if necessary.

getservbyname(“ftp”, “tcp”) = 0x7fcc5248b8c0

The servent structure is defined in as follows:

struct servent {
char *s_name; /* official service name */
char **s_aliases; /* alias list */
int s_port; /* port number */
char *s_proto; /* protocol to use */

Stallman, Richard: The Realization