27 TEXWAKEUP Preference for initex3x.exe
You may place in the .INI file (or the environment variables) an environment
variable TEXWAKEUP, which, if it is set to any non-empty string,
will result in the DOS-extended formatter
issuing a beep (ASCII 7) code to the standard
output whenever TEX is expecting input.
This is useful if you run TEX in a Windows iconized MS-DOS session,
since you will get an audible signal when TEX is waiting for your input.
(Previous editions of initex3x.exe always beeped; this was not always
appropriate.)
The Windows formatter will restore and activate the window when a TEX
error occurs.