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digitalmars.D.learn - acquiring the contents of environment variables

reply jicman <jicman_member pathlink.com> writes:
Greetings!

Does D has a library that can acquire the content of the environment variables
of a system?  I know I can do a

set > c:\envvars.txt

and read that file and get "some" of the environment vars.  However, is there a
proper library that I can do this from D?  I searched through the internet and
most of the stuff I encountered were compiler variables, etc.

Any ideas?

thanks,

josé
Aug 17 2005
next sibling parent reply AJG <AJG_member pathlink.com> writes:
Hi,


Does D has a library that can acquire the content of the environment variables
of a system? 


I don't know if there's a phobos function for that. 


Any ideas?


What I do is:

http://www.opengroup.org/onlinepubs/009695399/functions/getenv.html

In addition, the external variable

extern char** environ;

Might be useful to you, to get them all at once.

http://www.opengroup.org/onlinepubs/009695399/basedefs/xbd_chap08.html

Cheers,
--AJG.
Aug 17 2005
parent jicman <jicman_member pathlink.com> writes:
Thanks!  Yep, this will help me lots.

jic

AJG says...

Hi,


Does D has a library that can acquire the content of the environment variables
of a system? 


I don't know if there's a phobos function for that. 


Any ideas?


What I do is:

http://www.opengroup.org/onlinepubs/009695399/functions/getenv.html

In addition, the external variable

extern char** environ;

Might be useful to you, to get them all at once.

http://www.opengroup.org/onlinepubs/009695399/basedefs/xbd_chap08.html

Cheers,
--AJG.
Aug 17 2005
prev sibling next sibling parent reply Chris Sauls <ibisbasenji gmail.com> writes:
jicman wrote:

 Greetings!
 
 Does D has a library that can acquire the content of the environment variables
 of a system?  I know I can do a
 
 set > c:\envvars.txt
 
 and read that file and get "some" of the environment vars.  However, is there a
 proper library that I can do this from D?  I searched through the internet and
 most of the stuff I encountered were compiler variables, etc.


It isn't perfect for what you want (yet) because it doesn't yet enumerate the
full 
environment automatically, but it might give you an idea.  (What is it?)  Its
an 
Environment singleton I threw together for an unannounced project of mine,
code-name 
Mallard.  See what you think.  (Its the attachment.)

-- Chris Sauls
Aug 17 2005
parent jicman <jicman_member pathlink.com> writes:
Thanks.

Chris Sauls says...

This is a multi-part message in MIME format.
--------------020006040509030700090304
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit

jicman wrote:

 Greetings!
 
 Does D has a library that can acquire the content of the environment variables
 of a system?  I know I can do a
 
 set > c:\envvars.txt
 
 and read that file and get "some" of the environment vars.  However, is there a
 proper library that I can do this from D?  I searched through the internet and
 most of the stuff I encountered were compiler variables, etc.


It isn't perfect for what you want (yet) because it doesn't yet enumerate the
full 
environment automatically, but it might give you an idea.  (What is it?)  Its
an 
Environment singleton I threw together for an unannounced project of mine,
code-name 
Mallard.  See what you think.  (Its the attachment.)

-- Chris Sauls

--------------020006040509030700090304
Content-Type: text/plain;
 name="environment.d"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="environment.d"

/+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  Mallard 0.1
  An object-oriented CGI platform.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  Getting/setting environment variables via the Environment singleton.
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++/
module mallard.environment;

/+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  Imports
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++/
// standard imports
private import std.string   ;
private import std.c.stdlib ; // for getenv()

/+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  Aliases
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++/
alias std.string.toString stdToString;

/+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  Externs
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++/
private extern(C) int putenv(char*);

/+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  Constants
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++/
// CGI environment variable names - useful to make typos compile-time errors
public const char[]
  DOCUMENT_ROOT         = `DOCUMENT_ROOT`         ,
  GATEWAY_INTERFACE     = `GATEWAY_INTERFACE`     ,
  HTTP_ACCEPT           = `HTTP_ACCEPT`           ,
  HTTP_ACCEPT_CHARSET   = `HTTP_ACCEPT_CHARSET`   ,
  HTTP_ACCEPT_ENCODING  = `HTTP_ACCEPT_ENCODING`  ,
  HTTP_ACCEPT_LANGUAGE  = `HTTP_ACCEPT_LANGUAGE`  ,
  HTTP_CONNECTION       = `HTTP_CONNECTION`       ,
  HTTP_HOST             = `HTTP_HOST`             ,
  HTTP_KEEP_ALIVE       = `HTTP_KEEP_ALIVE`       ,
  HTTP_USER_AGENT       = `HTTP_USER_AGENT`       ,
  PATH_INFO             = `PATH_INFO`             ,
  PATH_TRANSLATED       = `PATH_TRANSLATED`       ,
  QUERY_STRING          = `QUERY_STRING`          ,
  REDIRECT_QUERY_STRING = `REDIRECT_QUERY_STRING` ,
  REDIRECT_STATUS       = `REDIRECT_STATUS`       ,
  REDIRECT_URL          = `REDIRECT_URL`          ,
  REMOTE_ADDR           = `REMOTE_ADDR`           ,
  REMOTE_PORT           = `REMOTE_PORT`           ,
  REQUEST_METHOD        = `REQUEST_METHOD`        ,
  REQUEST_URI           = `REQUEST_URI`           ,
  SCRIPT_FILENAME       = `SCRIPT_FILENAME`       ,
  SCRIPT_NAME           = `SCRIPT_NAME`           ,
  SERVER_ADDR           = `SERVER_ADDR`           ,
  SERVER_ADMIN          = `SERVER_ADMIN`          ,
  SERVER_NAME           = `SERVER_NAME`           ,
  SERVER_PORT           = `SERVER_PORT`           ,
  SERVER_PROTOCOL       = `SERVER_PROTOCOL`       ,
  SERVER_SIGNATURE      = `SERVER_SIGNATURE`      ,
  SERVER_SOFTWARE       = `SERVER_SOFTWARE`       ;

/+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  Singleton Environment
  TODO:
    Implement a method to enumerate the entire environment (or a least its
keys).
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++/
public abstract class Environment { static:

  /+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    Getting environment variable values.
    NOTE: Defaults to an empty string.
    USAGE:
      char[] var;
      var = Environment.get("some key");
      var = Environment["some key"];
  +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++/
  public char[] get (in char[] key) {
    return stdToString(getenv(toStringz(key)));
  }

  public alias get opIndex;

  /+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    Setting environment variable values.
    USAGE:
      char[] key = "some key", value = "some value";
      Environment.set(key, value);
      Environment[key] = value;
  +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++/
  public int set (in char[] key, in char[] value) {
    return putenv(toStringz(format("%s=%s", key, value)));
  }

  // can't use alias because the params are backward to support variable-length
keysets
  public int opIndexAssign (in char[] value, in char[] key) {
    return set(key, value);
  }

  /+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    An array of the CGI keys.  Can be useful for stepping through them all
easily.
    For an example, see the opApply overload below.
  +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++/
  public const char[][] STD_CGI_KEYS = [
    DOCUMENT_ROOT         ,
    GATEWAY_INTERFACE     ,
    HTTP_ACCEPT           ,
    HTTP_ACCEPT_CHARSET   ,
    HTTP_ACCEPT_ENCODING  ,
    HTTP_ACCEPT_LANGUAGE  ,
    HTTP_CONNECTION       ,
    HTTP_HOST             ,
    HTTP_KEEP_ALIVE       ,
    HTTP_USER_AGENT       ,
    PATH_INFO             ,
    PATH_TRANSLATED       ,
    QUERY_STRING          ,
    REDIRECT_QUERY_STRING ,
    REDIRECT_STATUS       ,
    REDIRECT_URL          ,
    REMOTE_ADDR           ,
    REMOTE_PORT           ,
    REQUEST_METHOD        ,
    REQUEST_URI           ,
    SCRIPT_FILENAME       ,
    SCRIPT_NAME           ,
    SERVER_ADDR           ,
    SERVER_ADMIN          ,
    SERVER_NAME           ,
    SERVER_PORT           ,
    SERVER_PROTOCOL       ,
    SERVER_SIGNATURE      ,
    SERVER_SOFTWARE       
  ];

  // For array-like syntax.  Some people like that.
  public alias STD_CGI_KEYS keys;

  /+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    Make the Environment foreach'able.
    Just steps through the standard CGI keys.
  +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++/
  // for just keys
  public int opApply(int delegate(inout char[]) dg) {
    int result ;

    foreach (char[] key; STD_CGI_KEYS) {
      result = dg(key);
      if (result)
        break;
    }
    return result;
  }

  // for key->value pairs
  public int opApply(int delegate(inout char[], inout char[]) dg) {
    int    result ;
    char[] key    ,
           value  ;

    foreach (char[] key; STD_CGI_KEYS) {
      value  = get (key       ) ;
      result = dg  (key, value) ;
      if (result)
        break;
    }
    return result;
  }

} // end singleton Environment

/+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++/
--------------020006040509030700090304--
Aug 17 2005
prev sibling parent reply Derek Parnell <derek psych.ward> writes:
On Wed, 17 Aug 2005 14:53:20 +0000 (UTC), jicman wrote:


 Greetings!
 
 Does D has a library that can acquire the content of the environment variables
 of a system?  I know I can do a
 
 set > c:\envvars.txt
 
 and read that file and get "some" of the environment vars.  However, is there a
 proper library that I can do this from D?  I searched through the internet and
 most of the stuff I encountered were compiler variables, etc.
 
 Any ideas?
 


I've used these snippets ...

extern (C)
{
        char*   getenv  (char *);
        int     putenv  (char *);
}

//-------------------------------------------------------
char[] GetEnv(char[] pSymbol)
//-------------------------------------------------------
{
    return std.string.toString(getenv(pSymbol));
}


putenv(envname ~ "=" ~ whatever);

-- 
Derek Parnell
Melbourne, Australia
18/08/2005 7:01:53 AM
Aug 17 2005
parent jicman <jicman_member pathlink.com> writes:
Thanks.

Derek Parnell says...

On Wed, 17 Aug 2005 14:53:20 +0000 (UTC), jicman wrote:


 Greetings!
 
 Does D has a library that can acquire the content of the environment variables
 of a system?  I know I can do a
 
 set > c:\envvars.txt
 
 and read that file and get "some" of the environment vars.  However, is there a
 proper library that I can do this from D?  I searched through the internet and
 most of the stuff I encountered were compiler variables, etc.
 
 Any ideas?
 


I've used these snippets ...

extern (C)
{
        char*   getenv  (char *);
        int     putenv  (char *);
}

//-------------------------------------------------------
char[] GetEnv(char[] pSymbol)
//-------------------------------------------------------
{
    return std.string.toString(getenv(pSymbol));
}


putenv(envname ~ "=" ~ whatever);

-- 
Derek Parnell
Melbourne, Australia
18/08/2005 7:01:53 AM
Aug 17 2005