#include <netdb.h> struct servent *getservent(void); struct servent *getservbyname(const char *name, const char *proto); struct servent *getservbyport(int port, const char *proto); void setservent(int stayopen); void endservent(void);
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.
The getservbyport() function returns a servent structure for the entry from the database that matches the port port (given in network byte order) using protocol proto. If proto is NULL, any protocol will be matched. A connection is opened to the database if necessary.
The setservent() function opens a connection to the database, and sets the next entry to the first entry. If stayopen is non-zero, then the connection to the database will not be closed between calls to one of the getserv*() functions.
The endservent() function closes the connection to the database.
The servent structure is defined in <netdb.h> 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 */ }
The members of the servent structure are: