Subversion Repositories openrisc

.\" Copyright (c) 1983, 1991, 1993

.\"     The Regents of the University of California.  All rights reserved.

.\"

.\" Redistribution and use in source and binary forms, with or without

.\" modification, are permitted provided that the following conditions

.\" are met:

.\" 1. Redistributions of source code must retain the above copyright

.\"    notice, this list of conditions and the following disclaimer.

.\" 2. Redistributions in binary form must reproduce the above copyright

.\"    notice, this list of conditions and the following disclaimer in the

.\"    documentation and/or other materials provided with the distribution.

.\" 3. All advertising materials mentioning features or use of this software

.\"    must display the following acknowledgement:

.\"     This product includes software developed by the University of

.\"     California, Berkeley and its contributors.

.\" 4. Neither the name of the University nor the names of its contributors

.\"    may be used to endorse or promote products derived from this software

.\"    without specific prior written permission.

.\"

.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND

.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE

.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

.\" SUCH DAMAGE.

.\"

.\"     From: @(#)getservent.3  8.3 (Berkeley) 1/12/94

.\"     $Id: getservent.3,v 1.2 2001-09-27 12:01:53 chris Exp $

.\"

.Dd July 9, 1995

.Dt GETSERVENT 3

.Os BSD 4.2

.Sh NAME

.Nm getservent ,

.Nm getservbyport ,

.Nm getservbyname ,

.Nm setservent ,

.Nm endservent

.Nd get service entry

.Sh SYNOPSIS

.Fd #include 

.Ft struct servent *

.Fn getservent

.Ft struct servent *

.Fn getservbyname "const char *name" "const char *proto"

.Ft struct servent *

.Fn getservbyport "int port" "const char *proto"

.Ft void

.Fn setservent "int stayopen"

.Ft void

.Fn endservent void

.Sh DESCRIPTION

The

.Fn getservent ,

.Fn getservbyname ,

and

.Fn 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,

.Pa /etc/services .

.Bd -literal -offset indent

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 */

};

.Ed

.Pp

The members of this structure are:

.Bl -tag -width s_aliases

.It Fa s_name

The official name of the service.

.It Fa s_aliases

A zero terminated list of alternate names for the service.

.It Fa s_port

The port number at which the service resides.

Port numbers are returned in network byte order.

.It Fa s_proto

The name of the protocol to use when contacting the

service.

.El

.Pp

The

.Fn getservent

function

reads the next line of the file, opening the file if necessary.

.Pp

The

.Fn setservent

function

opens and rewinds the file.  If the

.Fa stayopen

flag is non-zero,

the net data base will not be closed after each call to

.Fn getservbyname

or

.Fn getservbyport .

.Pp

The

.Fn endservent

function

closes the file.

.Pp

The

.Fn getservbyname

and

.Fn getservbyport

functions

sequentially search from the beginning

of the file until a matching

protocol name or

port number is found,

or until

.Dv EOF

is encountered.

If a protocol name is also supplied (non-

.Dv NULL ) ,

searches must also match the protocol.

.ne 1i

.Sh FILES

.Bl -tag -width /etc/services -compact

.It Pa /etc/services

.El

.Sh DIAGNOSTICS

Null pointer

(0) returned on

.Dv EOF

or error.

.Sh SEE ALSO

.Xr getprotoent 3 ,

.Xr services 5

.Sh HISTORY

The

.Fn getservent ,

.Fn getservbyport ,

.Fn getservbyname ,

.Fn setservent ,

and

.Fn endservent

functions appeared in

.Bx 4.2 .

.Sh 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.