from the ANSI standard

[unix-history] / usr / src / lib / libc / net / getprotoent.3

.\" Copyright (c) 1983 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms are permitted
.\" provided that the above copyright notice and this paragraph are
.\" duplicated in all such forms and that any documentation,
.\" advertising materials, and other materials related to such
.\" distribution and use acknowledge that the software was developed
.\" by the University of California, Berkeley.  The name of the
.\" University may not be used to endorse or promote products derived
.\" from this software without specific prior written permission.
.\" THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
.\" IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
.\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
.\"
.\"     @(#)getprotoent.3       6.4 (Berkeley) %G%
.\"
.TH GETPROTOENT 3 ""
.UC 5
.SH NAME
getprotoent, getprotobynumber, getprotobyname, setprotoent,
endprotoent \- get protocol entry
.SH SYNOPSIS
.nf
.ft B
.B #include <netdb.h>
.PP
.ft B
struct protoent *getprotoent()
.PP
.ft B
struct protoent *getprotobyname(name)
char *name;
.PP
.ft B
struct protoent *getprotobynumber(proto)
int proto;
.PP
.ft B
setprotoent(stayopen)
int stayopen
.PP
.ft B
endprotoent()
.fi
.SH DESCRIPTION
.IR Getprotoent ,
.IR getprotobyname ,
and
.I getprotobynumber
each return a pointer to an object with the
following structure
containing the broken-out
fields of a line in the network protocol data base,
.IR /etc/protocols .
.RS
.PP
.nf
struct  protoent {
       char    *p_name;        /* official name of protocol */
       char    **p_aliases;    /* alias list */
       int     p_proto;        /* protocol number */
};
.ft R
.ad
.fi
.RE
.PP
The members of this structure are:
.TP \w'p_aliases'u+2n
p_name
The official name of the protocol.
.TP \w'p_aliases'u+2n
p_aliases
A zero terminated list of alternate names for the protocol.
.TP \w'p_aliases'u+2n
p_proto
The protocol number.
.PP
.I Getprotoent
reads the next line of the file, opening the file if necessary.
.PP
.I Setprotoent
opens and rewinds the file.  If the
.I stayopen
flag is non-zero,
the net data base will not be closed after each call to 
.I getprotobyname
or
.IR getprotobynumber .
.PP
.I Endprotoent
closes the file.
.PP
.I Getprotobyname
and
.I getprotobynumber
sequentially search from the beginning
of the file until a matching
protocol name or
protocol number is found,
or until EOF is encountered.
.SH FILES
/etc/protocols
.SH "SEE ALSO"
protocols(5)
.SH DIAGNOSTICS
Null pointer
(0) returned on EOF or error.
.SH BUGS
All information
is contained in a static area
so it must be copied if it is
to be saved.  Only the Internet
protocols are currently understood.