casacore
EnvVar.h
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1//# EnvVar.h: Environment variables class
2//# Copyright (C) 1993,1994,1995,1999,2002
3//# Associated Universities, Inc. Washington DC, USA.
4//#
5//# This library is free software; you can redistribute it and/or modify it
6//# under the terms of the GNU Library General Public License as published by
7//# the Free Software Foundation; either version 2 of the License, or (at your
8//# option) any later version.
9//#
10//# This library is distributed in the hope that it will be useful, but WITHOUT
11//# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12//# FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public
13//# License for more details.
14//#
15//# You should have received a copy of the GNU Library General Public License
16//# along with this library; if not, write to the Free Software Foundation,
17//# Inc., 675 Massachusetts Ave, Cambridge, MA 02139, USA.
18//#
19//# Correspondence concerning AIPS++ should be addressed as follows:
20//# Internet email: aips2-request@nrao.edu.
21//# Postal address: AIPS++ Project Office
22//# National Radio Astronomy Observatory
23//# 520 Edgemont Road
24//# Charlottesville, VA 22903-2475 USA
25//#
26//# $Id$
27
28#ifndef CASA_ENVVAR_H
29#define CASA_ENVVAR_H
30
31#include <casacore/casa/aips.h>
32#include <casacore/casa/BasicSL/String.h>
33
34namespace casacore { //# NAMESPACE CASACORE - BEGIN
35
36// <summary>
37// This class allows for getting enviroment variables
38// </summary>
39
40// <use visibility=export>
41// <reviewed reviewer="Paul Shannon" date="1995/02/08" tests="tEnvVar" demos="">
42
43// <synopsis>
44// Environment variables are familiar to every Unix, MSDOS and VMS
45// computer user. This class makes it convenient to get and
46// enquire about environment variables from within a C++ program.
47// </synopsis>
48
49// <example>
50// Check if an environment variable is defined.
51// If so, get its value.
52// <srcblock>
53// if (EnvironmentVariable::isDefined ("PATH")) {
54// cout << EnvironmentVariable::get ("PATH") << endl;
55// }
56// </srcblock>
57// </example>
58
59// <todo asof=1994/02/08>
60// </todo>
61
63{
64public:
65 // Is environment variable with given name defined?
66 static Bool isDefined (const String& name);
67
68 // Get the value of environment variable with given name.
69 // If not defined, return an empty String.
70 static String get (const String& name);
71
72 // Define environment variable.
73 // If it already exists, its value will be overwritten.
74 static void set (const String& name, const String& value);
75
76private:
77 // This class is not meant to be constructed.
79};
80
81
82
83} //# NAMESPACE CASACORE - END
84
85#endif
86
static void set(const String &name, const String &value)
Define environment variable.
EnvironmentVariable()
This class is not meant to be constructed.
static String get(const String &name)
Get the value of environment variable with given name.
static Bool isDefined(const String &name)
Is environment variable with given name defined?
String: the storage and methods of handling collections of characters.
Definition: String.h:225
this file contains all the compiler specific defines
Definition: mainpage.dox:28
bool Bool
Define the standard types used by Casacore.
Definition: aipstype.h:42
LatticeExprNode value(const LatticeExprNode &expr)
This function returns the value of the expression without a mask.