Hi, I am trying to run few instances of IDL runtime with ENVI function (GLT_DOIT) simultaneously. What i realise is that these instances all write to a single temp file envi.tmp0-bsq. This fails almost all runtime instances. Does ENVI check for presence of file before dumping data to the temp file? Is there a way to get around this? Can I change to different temp directories for different instance for example? Thanks for any help.