ref: 75c92428225428c8fde2d015f010e608a0b12f1d
dir: purgatorio/man/2/srv
.TH SRV 2
.SH NAME
srv \- network name and address translation when hosted
.SH SYNOPSIS
.EX
include "srv.m"
srv := load Srv Srv->PATH;
Srv: module
{
init: fn();
iph2a: fn(host: string): list of string;
ipa2h: fn(addr: string): list of string;
ipn2p: fn(protocol, service: string): string;
};
.EE
.SH DESCRIPTION
.B Srv
provides access to the host operating system's
name and address translation when Inferno is running hosted.
The module's implementation is usually built-in to
.IR emu (1),
and then only on some platforms.
It uses the Internet name resolution services of the host operating system
(eg,
.B gethostbyname
on Unix systems).
Its services are normally only used internally by
.IR cs (8)
and
.IR dns (8),
and even they give priority to data in
.IR services (6)
and
.IR dns (6)
if available.
Other Inferno applications normally give network addresses to the functions of
.IR dial (2),
and they are then translated automatically, using the services of
.IR cs (8).
.PP
.B Init
must be called before any other function is used.
.PP
Given a host name,
.B iph2a
returns a list of its Internet addresses (if any).
Given an Internet address,
.B ipa2h
returns a list of host names (if any) that have that address.
The results are only as accurate as the host system's name service.
.PP
.B Ipn2p
returns the port number (as a string) for the given
.I service
when accessed using a particular protocol
.I protocol
(typically
.B tcp
or
.BR udp ).
.SH SOURCE
.B /emu/port/srv.c
.SH SEE ALSO
.IR sys-file2chan (2),
.IR cs (8),
.IR dns (8)