http://www.purl.org/tcl/home/man/tcl8.4/TclCmd/tell.htm ---- * '''tell and flush''' If you are using tell and you do reads and writes in between your calls to tell, you usually will have to do a flush or your tell will fail with a -1 return value. This is because the Tcl Channel code cannot ensure an accurate 'tell' value until you flush out pending i/o on your open channel. -mikeH * '''tell and open using "a", "a+", APPEND , etc..''' If you are using tell in combination with a channel opened in an APPEND mode, keep in mind that for each write performed, your file position is going to be placed at the end of the file. Tcl is reflecting the C library behaviour (which it should do if you think about it). ---- [Tcl syntax help] - [Arts and crafts of Tcl-Tk programming] - [Category Command]