diff --git a/src/utils/execmd.cpp b/src/utils/execmd.cpp
index 9cefa6e7..79798d21 100644
--- a/src/utils/execmd.cpp
+++ b/src/utils/execmd.cpp
@@ -1,5 +1,5 @@
 #ifndef lint
-static char rcsid[] = "@(#$Id: execmd.cpp,v 1.6 2005-03-17 14:02:05 dockes Exp $ (C) 2004 J.F.Dockes";
+static char rcsid[] = "@(#$Id: execmd.cpp,v 1.7 2005-11-18 13:52:48 dockes Exp $ (C) 2004 J.F.Dockes";
 #endif
 #ifndef TEST_EXECMD
 #include <unistd.h>
@@ -21,11 +21,15 @@ static char rcsid[] = "@(#$Id: execmd.cpp,v 1.6 2005-03-17 14:02:05 dockes Exp $
 using namespace std;
 #define MAX(A,B) (A>B?A:B)
 
-int
-ExecCmd::doexec(const string &cmd, const list<string>& args,
+void  ExecCmd::putenv(const string &ea)
+{
+    env.push_back(ea);
+}
+
+int ExecCmd::doexec(const string &cmd, const list<string>& args,
 		const string *input, string *output)
 {
-    {
+    { // Debug and logging
 	string command = cmd + " ";
 	for (list<string>::const_iterator it = args.begin();it != args.end();
 	     it++) {
@@ -186,6 +190,10 @@ ExecCmd::doexec(const string &cmd, const list<string>& args,
 	    while (argv[i]) cerr << argv[i++] << endl;}
 #endif
 
+	for (it = env.begin(); it != env.end(); it++) {
+	    ::putenv(it->c_str());
+	}
+	
 	execvp(cmd.c_str(), (char *const*)argv);
 	// Hu ho
 	LOGERR(("ExecCmd::doexec: execvp(%s) failed. errno %d\n", cmd.c_str(),
@@ -224,7 +232,12 @@ int main(int argc, const char **argv)
     input = data;
     string *ip = 0;
     //ip = &input;
+    mexec.putenv("TESTVARIABLE1=TESTVALUE1");
+    mexec.putenv("TESTVARIABLE2=TESTVALUE2");
+    mexec.putenv("TESTVARIABLE3=TESTVALUE3");
+
     int status = mexec.doexec(cmd, l, ip, &output);
+
     fprintf(stderr, "Status: 0x%x\n", status);
     cout << "Output:" << output << endl;
     exit (status >> 8);
diff --git a/src/utils/execmd.h b/src/utils/execmd.h
index 4ce19f6a..77a679ff 100644
--- a/src/utils/execmd.h
+++ b/src/utils/execmd.h
@@ -1,17 +1,40 @@
 #ifndef _EXECMD_H_INCLUDED_
 #define _EXECMD_H_INCLUDED_
-/* @(#$Id: execmd.h,v 1.2 2005-03-17 14:02:06 dockes Exp $  (C) 2004 J.F.Dockes */
+/* @(#$Id: execmd.h,v 1.3 2005-11-18 13:52:48 dockes Exp $  (C) 2004 J.F.Dockes */
 
 #include <string>
 #include <list>
 
+/**
+ Execute command possibly taking both input and output (will do
+ asynchronous io as appropriate for things to work).
+*/
 class ExecCmd {
  public:
-    //    ExecCmd() : argv(0) {};
-    //    ~ExeCmd() {delete [] argv;}
-    int doexec(const std::string &cmd, const std::list<std::string>& a, 
+    /**
+     * Execute command. Both input and output can be specified, and
+     * asynchronous io is used to prevent blocking. This wont work if
+     * input and output need to be synchronized (ie: Q/A), but ok for
+     * filtering.
+     * @param cmd the program to execute. This must be an absolute file name 
+     *   or exist in the PATH.
+     * @param args the argument list (NOT including argv[0]).
+     * @param input Input to send to the command.
+     * @param output Output from the command.
+     * @return the exec ouput status (0 if ok).
+     */
+    int doexec(const std::string &cmd, const std::list<std::string>& args, 
 	       const std::string *input = 0, 
 	       std::string *output = 0);
+    /** 
+     * Add/replace environment variable before executing command. This should 
+     * be called before doexec of course.
+     * @param envassign an environment assignment string (name=value)
+     */
+    void putenv(const std::string &envassign);
+
+ private:
+    std::list<std::string> env;
 };