* arguments have not been converted. */
    TclFile inputFile,		/* If non-NULL, gives the file to use as input
				 * for the child process. If inputFile file is
				 * not readable or is NULL, the child will
				 * receive no standard input. */
    TclFile outputFile,		/* If non-NULL, gives the file that receives
				 * output from the child process. If
				 * outputFile file is not writeable or is
				 * NULL, output from the child will be
				 * discarded. */
    TclFile errorFile,		/* If non-NULL, gives the file that receives
				 * errors from the child process. If errorFile
				 * file is not writeable or is NULL, errors
				 * from the child will be discarded. errorFile
				 * may be the same as outputFile. */
    Tcl_Pid *pidPtr)		/* If this function is successful, pidPtr is
				 * filled with the process id of the child
				 * process. */
{
    int result, applType, createFlags;

    int action)
{
    PipeInfo *infoPtr = (PipeInfo *) instanceData;

    /*
     * We do not access firstPipePtr in the thread structures. This is not for
     * all pipes managed by the thread, but only those we are watching.
     * Removal of the filevent handlers before transfer thus takes care of
     * this structure.
     */

    Tcl_MutexLock(&pipeMutex);
    if (action == TCL_CHANNEL_THREAD_INSERT) {
	/*
	 * We can't copy the thread information from the channel when the