netbsd man page for getservent

GETSERVENT(3)						   BSD Library Functions Manual 					     GETSERVENT(3)

NAME
     getservent, getservbyport, getservbyname, setservent, endservent -- get service entry

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <netdb.h>

     struct servent *
     getservent();

     struct servent *
     getservbyname(const char *name, const char *proto);

     struct servent *
     getservbyport(int port, const char *proto);

     void
     setservent(int stayopen);

     void
     endservent(void);

DESCRIPTION
     The getservent(), getservbyname(), and getservbyport() functions each return a pointer to an object with the following structure containing
     the broken-out fields of a line in the network services data base, /etc/services.

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

     The members of this structure are:

     s_name	The official name of the service.

     s_aliases	A NULL terminated list of alternative names for the service.

     s_port	The port number at which the service resides.  Port numbers must be given and are returned in network byte order.

     s_proto	The name of the protocol to use when contacting the service.

     The getservent() function reads the next line of the file, opening the file if necessary.

     The setservent() function opens and rewinds the file.  If the stayopen flag is non-zero, the net data base will not be closed after each call
     to getservbyname() or getservbyport().

     The endservent() function closes the file.

     The getservbyname() and getservbyport() functions sequentially search from the beginning of the file until a matching protocol name or port
     number is found, or until EOF is encountered.  If a protocol name is also supplied (non-NULL), searches must also match the protocol.

FILES
     /etc/services

DIAGNOSTICS
     Null pointer (0) returned on EOF or error.

SEE ALSO
     getprotoent(3), services(5)

HISTORY
     The getservent(), getservbyport(), getservbyname(), setservent(), and endservent() functions appeared in 4.2BSD.

BUGS
     These functions use static data storage; if the data is needed for future use, it should be copied before any subsequent calls overwrite it.
     Expecting port numbers to fit in a 32 bit quantity is probably naive.

BSD
								   May 25, 1995 							       BSD