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ghostname_unix.cpp
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1//
2// Copyright (C) 2001-2021 Graeme Walker <graeme_walker@users.sourceforge.net>
3//
4// This program is free software: you can redistribute it and/or modify
5// it under the terms of the GNU General Public License as published by
6// the Free Software Foundation, either version 3 of the License, or
7// (at your option) any later version.
8//
9// This program is distributed in the hope that it will be useful,
10// but WITHOUT ANY WARRANTY; without even the implied warranty of
11// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12// GNU General Public License for more details.
13//
14// You should have received a copy of the GNU General Public License
15// along with this program. If not, see <http://www.gnu.org/licenses/>.
16// ===
17///
18/// \file ghostname_unix.cpp
19///
20
21#include "gdef.h"
22#include "ghostname.h"
23#include "gstr.h"
24#include "genvironment.h"
25#include <sys/utsname.h>
26
27std::string G::hostname()
28{
29 struct utsname info {} ;
30 int rc = ::uname( &info ) ;
31 if( rc == -1 )
32 return std::string() ;
33
34 std::string name = std::string( info.nodename ) ;
35 std::string::size_type pos = name.find( '.' ) ;
36 if( pos != std::string::npos )
37 name = name.substr( 0U , pos ) ;
38
39 // pathologically "uname -n" can be empty, so
40 // allow "export HOSTNAME=localhost" as a
41 // workround
42 //
43 if( name.empty() )
44 {
45 name = Str::printable( Environment::get("HOSTNAME",std::string()) , '_' ) ;
46 }
47
48 return name ;
49}
50
std::string hostname()
Returns the hostname.