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Message-ID: <000301c24241$827cf550$33bc07d5@StrubeNB>
From: "Hans Werner Strube" <strube AT physik3 DOT gwdg DOT de>
To: <cygwin AT cygwin DOT com>
Subject: putenv uses volatile memory
Date: Mon, 12 Aug 2002 22:47:43 +0200
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Cygwin version: 1.3.12-2.
Function putenv() obviously stores only the address of the argument
string, not its contents. Thus it works reliably only for static, unchanged
argument strings. Consider the command sequence
        char env[256];
        strcpy(env,"EINS=one");
        putenv(env);
        strcpy(env,"ZWEI=two");
/*      putenv(env);*/
With or without the last putenv(), only the environment ZWEI=two
exists now, the first one has been overwritten.
Workaround: #define putenv(x) putenv(strdup(x))




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