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/*#######################################################################
# RDOS operating system
# Copyright (C) 1988-2006, Leif Ekblad
#
# This library is free software; you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published
# by the Free Software Foundation; either version 2.1 of the License, or
# (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#
# The author of this program may be contacted at leif@rdos.net
#
# getenv.c
# getenv function implementation
#
##########################################################################*/
/*
FUNCTION
<<getenv>>---look up environment variable
INDEX
getenv
INDEX
environ
ANSI_SYNOPSIS
#include <stdlib.h>
char *getenv(const char *<[name]>);
TRAD_SYNOPSIS
#include <stdlib.h>
char *getenv(<[name]>)
char *<[name]>;
DESCRIPTION
<<getenv>> searches the list of environment variable names and values
(using the global pointer ``<<char **environ>>'') for a variable whose
name matches the string at <[name]>. If a variable name matches,
<<getenv>> returns a pointer to the associated value.
RETURNS
A pointer to the (string) value of the environment variable, or
<<NULL>> if there is no such environment variable.
PORTABILITY
<<getenv>> is ANSI, but the rules for properly forming names of environment
variables vary from one system to another.
This function is not thread-safe, but does it need to be??
There is an reentrant class that should be used if reentrance is required
*/
#include <stdlib.h>
#include <stddef.h>
#include <string.h>
#include <rdos.h>
static char envbuf[256];
char *getenv(const char *name)
{
int handle;
char *ptr = 0;
handle = RdosOpenSysEnv();
if (handle)
{
if (RdosFindEnvVar(handle, name, envbuf))
ptr = envbuf;
}
RdosCloseEnv(handle);
return ptr;
}
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