Re: Escape delay

Chris Stone (chriss@brttsg.demon.co.uk) wrote: : In article: <1995Jan30.221820.10688@mswinsor> wmark@mswinsor (Mark S. Winsor) writes: : > : > What is the method for lowering the ESC delay in Informix? It doesn't seem : > to use the Unix env variable. We have users complaining of the slowness : > of the software, but it seems to be just a perception based on the ESC : > slowness. I'd prefer not to recode the application if it could be avoided. : > : > : I am curious about this also. The delay seems to only occur in VT-nnn : mode, including XTerm. There is no delay when using Wyse-nn emulation : however... I have checked termcap/info and can see nothing obvious. It has to do with the ambiguity of the ESC character. Cursor keys and function keys on the VTxxx all send a sequence beginning with ESC. The Wyse terminals don't. But on a VT100 terminal, if the program receives an ESC character it doesn't know if it is the start of a function/cursor key sequence, or just the ESC key. So it uses a short delay before it decides, to see whether more characters arrive. Occasionally, on a heavily loaded system, the sequence ^[[A for instance arrives so slowly that the program doesn't recognize it as a cursor key. I've seen this happen on an old DEC VAX with about 50 students pounding away. Informix doesn't have any adjustable delay that I'm aware of, at least in their own curses implementation. It may be available on some platforms where Informix supports terminfo. Somebody please correct me if you have better information. -- Jeff Sturm jsturm@mail.msen.com