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GETSERVENT(3)	       FreeBSD 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 zero terminated list of alternate names for the service.

     s_port	The port number	at which the service resides.  Port numbers
		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 (which must	be specified in	network	byte order) 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 a thread-specific 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.

FreeBSD	10.1			 July 9, 1995			  FreeBSD 10.1

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | FILES | DIAGNOSTICS | SEE ALSO | HISTORY | BUGS

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