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Diffstat (limited to 'lib/libc/net/getnetent.3')
-rw-r--r-- | lib/libc/net/getnetent.3 | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/lib/libc/net/getnetent.3 b/lib/libc/net/getnetent.3 new file mode 100644 index 0000000..f408f76 --- /dev/null +++ b/lib/libc/net/getnetent.3 @@ -0,0 +1,172 @@ +.\" 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. +.\" 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. +.\" +.\" @(#)getnetent.3 8.1 (Berkeley) 6/4/93 +.\" $FreeBSD$ +.\" +.Dd June 4, 1993 +.Dt GETNETENT 3 +.Os +.Sh NAME +.Nm getnetent , +.Nm getnetbyaddr , +.Nm getnetbyname , +.Nm setnetent , +.Nm endnetent +.Nd get network entry +.Sh LIBRARY +.Lb libc +.Sh SYNOPSIS +.In netdb.h +.Ft struct netent * +.Fn getnetent void +.Ft struct netent * +.Fn getnetbyname "const char *name" +.Ft struct netent * +.Fn getnetbyaddr "uint32_t net" "int type" +.Ft void +.Fn setnetent "int stayopen" +.Ft void +.Fn endnetent void +.Sh DESCRIPTION +The +.Fn getnetent , +.Fn getnetbyname , +and +.Fn getnetbyaddr +functions +each return a pointer to an object with the +following structure describing an internet network. +This structure contains either the information obtained +from the nameserver, +.Xr named 8 , +broken-out fields of a line in the network data base +.Pa /etc/networks , +or entries supplied by the +.Xr yp 8 +system. +The order of the lookups is controlled by the +`networks' entry in +.Xr nsswitch.conf 5 . +.Pp +.Bd -literal -offset indent +struct netent { + char *n_name; /* official name of net */ + char **n_aliases; /* alias list */ + int n_addrtype; /* net number type */ + uint32_t n_net; /* net number */ +}; +.Ed +.Pp +The members of this structure are: +.Bl -tag -width n_addrtype +.It Fa n_name +The official name of the network. +.It Fa n_aliases +A zero terminated list of alternate names for the network. +.It Fa n_addrtype +The type of the network number returned; currently only AF_INET. +.It Fa n_net +The network number. +Network numbers are returned in machine byte +order. +.El +.Pp +The +.Fn getnetent +function +reads the next line of the file, opening the file if necessary. +.Pp +The +.Fn setnetent +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 getnetbyname +or +.Fn getnetbyaddr . +.Pp +The +.Fn endnetent +function +closes the file. +.Pp +The +.Fn getnetbyname +function +and +.Fn getnetbyaddr +sequentially search from the beginning +of the file until a matching +net name or +net address and type is found, +or until +.Dv EOF +is encountered. +The +.Fa type +argument +must be +.Dv AF_INET . +Network numbers are supplied in host order. +.Sh FILES +.Bl -tag -width /etc/nsswitch.conf -compact +.It Pa /etc/networks +.It Pa /etc/nsswitch.conf +.It Pa /etc/resolv.conf +.El +.Sh DIAGNOSTICS +Null pointer +(0) returned on +.Dv EOF +or error. +.Sh SEE ALSO +.Xr networks 5 +.Pp +.%T RFC 1101 +.Sh HISTORY +The +.Fn getnetent , +.Fn getnetbyaddr , +.Fn getnetbyname , +.Fn setnetent , +and +.Fn endnetent +functions appeared in +.Bx 4.2 . +.Sh BUGS +The data space used by +these functions is thread-specific; if future use requires the data, it should be +copied before any subsequent calls to these functions overwrite it. +Only Internet network +numbers are currently understood. +Expecting network numbers to fit +in no more than 32 bits is probably +naive. |