1.\" $OpenBSD: services.5,v 1.14 2021/05/05 11:49:17 sthen Exp $ 2.\" $NetBSD: services.5,v 1.3 1994/11/30 19:31:31 jtc Exp $ 3.\" 4.\" Copyright (c) 1983, 1991, 1993 5.\" The Regents of the University of California. All rights reserved. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 3. Neither the name of the University nor the names of its contributors 16.\" may be used to endorse or promote products derived from this software 17.\" without specific prior written permission. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29.\" SUCH DAMAGE. 30.\" 31.\" @(#)services.5 8.1 (Berkeley) 6/5/93 32.\" 33.Dd $Mdocdate: May 5 2021 $ 34.Dt SERVICES 5 35.Os 36.Sh NAME 37.Nm services 38.Nd service name database 39.Sh DESCRIPTION 40The 41.Nm 42file contains information regarding the known services available in the 43Internet. 44For each service, a single line should be present with the 45following information: 46.Bd -unfilled -offset indent 47official service name 48port number 49protocol name 50aliases 51.Ed 52.Pp 53Items are separated by any number of blanks and/or tab characters. 54The port number and protocol name are considered a single item; a slash 55.Pq Ql / 56is used to separate the port and protocol (e.g., 57.Dq 512/tcp ) . 58.Pp 59A hash mark 60.Pq Ql # 61indicates the beginning of a comment; subsequent characters up to the 62end of the line are not interpreted by the routines which search the file. 63.Pp 64Service names may contain any printable character other than a 65field delimiter, newline, or comment character. 66.Pp 67To protect service ports from being used for dynamic port assignment, 68.Xr rc 8 69reads 70.Nm 71at boot and uses the contents to populate 72.Va net.inet.tcp.baddynamic 73and 74.Va net.inet.udp.baddynamic . 75.Pp 76While it is the policy of IANA to assign a single well-known port number 77for both TCP and UDP, to avoid reducing the dynamic port range unnecessarily, 78the unused entries are not always listed in 79.Nm . 80.Sh FILES 81.Bl -tag -width /etc/services -compact 82.It Pa /etc/services 83.El 84.Sh SEE ALSO 85.Xr getservent 3 86.Sh HISTORY 87The 88.Nm 89file format appeared in 90.Bx 4.2 . 91.Sh BUGS 92A name server should be used instead of a static file. 93Lines in 94.Pa /etc/services 95are limited to 96.Dv BUFSIZ 97characters (currently 1024). 98Longer lines will be ignored. 99